The district attorney R. Frank Marlowe (Raymond Burr, who later went on to star as the famed Perry Mason in a long-running, popular TV show) and authorities drag the lake for the drowning victim's mysterious companion, but the boatkeeper has his doubts:

You can drag that lake until you're blue in the face and you won't find him....well, I figure he left here in an auto. When I went up to my cabin last night, around supper time, there was a little old coupe parked off in the woods up there apiece. Now about, uh, nine o'clock, somebody started up that auto and drove it off awfully fast.

Back at the Vickers' home, Angela's clean-cut friends greet Hawaiian-shirted George with an insightful joke: "Hey George, where ya been? Got another woman stashed around someplace?" With the prospects of marrying Angela clearly shattered with this new catastrophe, George knows his time is short and he must find some privacy and confess to Angela, but her friends won't let them cruise away in a speedboat without joining them. A portable radio resting on the dock broadcasts news of the investigation, but it is momentarily drowned out by the roar of watercraft engines: "...the district attorney Frank Marlowe's officers to investigate further. Less than an hour ago, the coroner and all the press...marks and bruises on her face and chin would indicate a struggle took place. The district attorney meanwhile is believed to have evidence that the girl's male companion may still be alive. Three Boy Scouts have reported that he got mad...physical upset...."

And newspaper reports about the "drowning over at Loon" appear to "build it up into a murder case." One of Angela's girlfriends named Francis, who may have "read too many murder mysteries," remarks: "The odds are the fella's still alive and he's drowned her." Mr. Vickers summons George into his presence in the living room for a little "personal" chat before dinner - not about the breaking news story but about his dubious marriage prospects. Angela hovers on the back patio behind them, and then sneaks in to listen:

Mr. Vickers: It's about you and Angela. There's talk going around about you getting married. Right now, I don't know whether I'm for you or against you. I don't know you well enough.
George: I know how you feel, Mr. Vickers. Who am I to think of marrying Angela? Angela has everything.
Mr. Vickers: The talk of marriage aside, the fact is that we know almost nothing about your background.
George: There's not much to know, but what there is I wanted to tell you myself. We, my family is - we are very poor people. My family devoted their lives to a kind of religious work conducting sidewalk services and street singing. I was part, part of all that until the law came along and said I - I ought to go to school. I only went to school until I was thirteen years old. You see, we didn't never have any, any money for anything so I left home. I was going to do something about it. I took any kind of job I could get. I was bus boy, elevator operator, caddy, I had no training, no, no education. Then I came here and went to work for my uncle. That's my background, Mr. Vickers. There's not very much there to recommend any approval. But I love Angela more than anything in the world. I'd do anything to make her happy. If it's right that I shouldn't see her anymore...? (Angela appears stunned)
Mr. Vickers: Easy boy. Forthrightness is a prime virtue. Let me tell you, I admire your frankness.
Angela: (speaking up and startling her father) I should apologize for eaves-dropping. I'm glad I listened. Well Dad, does that answer all your questions?
Mr. Vickers: All I ask is that you two don't do anything hasty. (He exits)
George: Let's get out somewhere.
Angela: We'll go for a drive.
George: I want to be alone with you, that's all I want.

They drive to a secluded spot - a dissolve to postmarked letters addressed to Alice Tripp being dropped on her bed reveal that investigators are interrogating Alice's landlady Mrs. Roberts about whether her tenant had any boyfriends - she divulges that the "sweet, quiet girl" said her most recent friend "was an Eastman - oh, but it couldn't be, not one of the Eastmans!" A motorcycle policeman (Mike Mahoney) trails the speeding convertible carrying Angela and George, and finds them "safe and sound" on a side road where they have hidden away. She is given a speeding ticket for the "third time this summer." After the cop pulls away, George seeks shelter from the world in her embrace as they share one of their last conversations together:

Angela: Darling, what is it?
George: I'm tired. I'm tired.
Angela: Yes, you must be.
George: Darling, let's never leave this place. Let's just stay here alone.
Angela: Don't let father upset you. I'm the one who counts.
George: You're the only one. The only one. People are gonna, they're gonna say things, I know it. Things about me, about me, I know. It's gonna make you stop loving me.
Angela (cradling his head in her arms): Shhh, don't talk like that. (The sounds of sirens are heard in the background. He naps and mumbles)
George: I was asleep.
Angela: You were dreaming. You were talking. You said, 'Not my fault.' And then you said something I couldn't make out. And then you said, 'Angela, don't hate me.' That was a bad dream, George, a false dream, because I'll always love you. (They hug each other) We'd better go now. Mother's liable to send out a posse for us.

Ominously, there are police cars parked in the Vickers driveway when they pull in. When Angela parts from him at the door after a lengthy goodbye kiss, she whispers:

Every time you leave me for a minute, it's like good-bye. I like to believe it means you can't live without me.

As sirens sound, George flees into the woods from the police and is quickly arrested and charged with Alice's murder and taken to be locked up in the jail in Warsaw - he pleads "not guilty" to the district attorney, R. Frank Marlowe. At the Vickers home, Angela is questioned and denies any knowledge of George's relations with Alice Tripp or the "double life" that George was leading. Mr. Vickers hires a lawyer to defend him at the first-degree murder trial, with the one stipulation that Angela's name will be kept out of the case: "I'll engage the boy's lawyers and if it appears he's innocent, I'll spend one hundred thousand dollars to defend him...If he is guilty, I won't spend a single cent to save him from the electric chair." From the shock of the revelation, Angela faints dead-away onto her bedroom floor - reflected in her full-length mirror.

George's hearing with his defense lawyers provides some credible evidence: "After I got her out on the lake, I couldn't go through with it. Then the boat turned over," but their defendant appears pre-occupied with thoughts of Angela. The D.A. Marlowe vehemently vows that "EASTMAN WILL GET CHAIR," as part of his own personal quest for power: "Experts Predict Conviction Will Speed Warsaw's Up-and-Coming District Attorney On His Road to Capitol." Likewise, Angela is consumed by her feelings for George, and reclines on a bed - watching flames destroy the newspapers' reports of the case that have been forbidden to her. Months pass - the Vickers vacate the summer lodge as fall winds and cold weather approach.

In the criminal trial in the courtroom, Marlowe charges that "George Eastman willfully and with malice and cruelty and deception murdered and sought to conceal from the knowledge and justice of the world the body of Alice Tripp. (To the jury) It will be for you, ladies and gentlemen, to decide what should be done with this man who has flouted every moral law, broken every commandment, who has found his infamy - murder." There is overwhelming circumstantial evidence in the trial brought against him by the prosecution's witnesses:

• A witness reports Alice's feelings for the defendant: "She was in love with him. Everybody knew that."
• Mr. Whiting (William Murphy) of Eastman Industries explains the 'no fraternization' rule
• Tripp's landlady recounts calling Alice to the telephone to speak to George
• Dr. Wyeland describes Alice speaking to a "man in a coupe" for a long time after leaving his office
• Eagle Scout camper (Robert Anderson) testifies that at nine o'clock, Eastman stumbled over him after swimming to shore - "his clothes were wet and he looked scared and shaky"
• The bus company employee/witness who had seen Eastman and Tripp quarreling at the bus station testifies that "they were quarreling and she said she wouldn't leave the depot unless he promised"
• The coroner (John Ridgley) reports that prior to her death by drowning, "apparently the young woman had been struck by a dull instrument with sufficient force to stun her"
• The boatkeeper, after telling George that the lake was deserted, describes how the boat-renter signed a false name - "he took the pencil and signed the name of Gilbert Edwards"

In the trial, George's defense attorney argues that although his client wished to murder her, he didn't actually commit the deed:

This boy is on trial for the act of murder - not for the thought of murder. Between the idea and the deed there's a world of difference. And if you find this boy guilty in desire but not guilty in deed, then he must walk out of this courtroom as free as you or I. However, since the prosecutor lacked evidence, he's given you prejudice; lacking facts, he's given you fantasy. Of all the witnesses he's paraded before you, not one actually saw what happened. I will now call to the stand an eyewitness - the only eyewitness - the only one who knows the truth, the whole truth. George Eastman, will you please take the stand?

On the witness stand, George's testimony is unconvincing and shaky as he recounts his thinking up until the moment the boat capsized. He solemnly swears that he didn't strike Alice, didn't throw her in to drown her, and that her death was an undesired fatal accident, although he admits to not doing much to save her:

George: When we got to the lake, I suggested we go rowing before it got dark.
Lawyer: Now tell me George, why did you give a false name to the boatkeeper?
George: We were going to spend the night at the lodge. And we weren't married, so I thought it would be better if we didn't give our right names.
Lawyer: Well, why at this time, did you engage the boat to row the girl out onto the lake?
George: In the back of my mind was the thought of drowning her, but I didn't want to think such things. I couldn't help myself, I couldn't.
Lawyer: So what happened after you rowed out onto the lake?
George: I knew then that I couldn't do it. I couldn't go through with it.
Lawyer: And then, you had a change of heart.
Marlowe: I object. He's leading the witness.
Judge: Objection sustained. Counsel will refrain from leading the witness.
Lawyer: Yes, your Honor. What happened then, George?
George: Oh, uh, it was when, uh, we decided to, we gotta get back to the lodge. She started talking about, about our getting married and what our life together would be like.
Lawyer: What was your reaction to that, to her talking that way?
George: She just looked at me. She knew it was hopeless. She accused me of wishing she was dead.
Lawyer: Did you, George? Did you wish she were dead?
George: NO! I didn't! I wasn't thinking of that anymore.
Lawyer: What were you thinking of at that moment?
George (subdued): I was thinking of somebody else.
Lawyer: Another girl. You were thinking that this other girl and her world were lost to you forever. What did you say to Alice's accusation?
George: I told her it wasn't true. I didn't want her to die.
Lawyer: Wasn't she alarmed, frightened?
George: She even said, 'Poor George!' Then she started toward me from the back of the boat. I told her not to. I told her stay where she was. But she didn't. She-she kept coming toward me and then she stumbled and started to fall and I started to get up, and then everything turned over, and in a second we were in the water. I was stunned. Something must have hit me as I fell in. It all happened so fast, I didn't know what I was doing.
Lawyer: George? Was Alice conscious when she fell into the water?
George: Yes, I could hear her scream. But I couldn't see her, because she was on the other side of the boat. So I swam around to get to the other side and she was - when I got there, she'd gone down. I never saw her again.
Lawyer: Do you solemnly swear before God that you did not strike Alice Tripp...
George: I do, I swear.
Lawyer: ...and that you did not throw her into that lake...
George: I did not.
Lawyer: ...and that it was an accident undesired by you.
George: I do. I do. I do.

As the trial proceeds, the fanatical district attorney brutally and brilliantly cross-examines George and effectively destroys his credibility:

Marlowe: Eastman, that night when you left that dinner party at the house at Bride's Lake to meet Alice Tripp in the bus station, do you remember leaving anything behind you?
George: No, I don't. I don't remember leaving anything.
Marlowe: I'm referring to your heart, Eastman. Did you leave that behind you? Did you, Eastman? Out there on that terrace in the moonlight. You left behind, didn't you, the girl you loved - and, with her, your hopes, your ambitions, your dreams? Didn't you, Eastman? You left behind everything in the world you ever wanted, including the girl you loved. But you planned to return to it, didn't you, Eastman? Answer me!
George: Yes.
Marlowe: Eastman? When you told them all that night that you were going to visit your mother, you were lying, weren't you?
George: Yes.
Marlowe: When you gave the boatkeeper a false name, you were lying again, weren't you?
George: Yes.
Marlowe: When you drove up to Loon Lake, what reason did you give Alice Tripp for parking so far away from the lodge?
George: Because we were out of gas.
Marlowe: Weren't you lying again?
George: Yes.
Marlowe: Lies. Isn't it a fact that every move you made was built on lies? Yet now, of course, when you're facing death in the electric chair, suddenly you can't tell anything but the truth, is that what you want the jury to believe?
George: All the same, it's true. (softly) I didn't kill her.
Marlowe: So you persist in lying about that, too.

The climax of the trial occurs when the rowboat is brought into the courtroom and soul-searching Eastman (sitting in the boat) has difficulty remembering and reconstructing the accident when the boat overturned and Alice "fell sideways into the water...There was a thud as if the edge of the boat came down and hit her on the head." Marlowe thrusts away with derogatory accusations:

Why couldn't you swim toward her instead of away from her?

When Eastman is asked to step out of the boat, his foot snags on a coil of rope in the boat - suggesting that when he tried to save Alice, his tangled foot prevented him from doing so. [However, there was no rope that snagged his foot in the earlier scene.] After he emerged from underwater, about fifteen or twenty feet away from Alice, Marlowe insinuates that Eastman deliberately didn't swim to save the girl:

You mean to tell me you couldn't swim this little distance to this poor weak girl and buoy her up 'til you could reach this boat just fifteen feet away. I'll tell you one thing, you know, you know you're lying. She was drowning and you just let her drown. She was sitting there defenseless in the back of the boat and you picked up this oar like this, and you crashed it down on that poor girl's head like this!

The D.A. dramatically smashes the rowboat oar across the boat, implying that George struck Alice with it, or shoved her down into the water with it, and made no effort to save her: "You pushed that poor girl into the lake and watched her drown. Isn't that the truth?" George cowers and murmurs: "No."

Not surprisingly, George is found guilty of first degree murder by the jury and sentenced to death. He wires a telegram to his mother with the bad news:

Hannah Eastman, Bethel Independent Mission, Kansas City, Mo., Mother I am convicted, George.

His mother visits George in prison - her appeal to the governor to stay his execution has been unsuccessful. With Rev. Morrison (Paul H. Frees), she encourages George to boldly face death, even though he is uncertain of his own guilt:

Hannah Eastman: Death is a little thing, George. You mustn't be afraid of it. You must fear now only for your immortal soul. Blessings on your soul, my son. You must make your peace with God.
George: I don't believe I am guilty of all this. I don't know. I wish I knew.
Hannah: If you are guilty, then I too am guilty. I must share your guilt.
George: Oh, mama, don't blame yourself.
Reverend: You know, they say only God and ourselves know what our sins and sorrows are. Perhaps in this case, only God knows. George, perhaps you've hidden the full truth of this even from yourself.
George: I don't want to hide it. I want to know.
Reverend: George, there's one thing you've never told anyone, even yourself. There's one point in your story that holds the answer you're looking for.
George: Yes.
Reverend: When you were on the lake with that poor girl and the boat capsized, and there was a moment when you might have saved her...
George: I wanted to save her, but I just couldn't.
Reverend: But whom were you thinking of, who were you thinking of just at that moment? Were you thinking of Alice? Were you thinking of the other girl? (George remains silent, unable to respond as he searches for the answer. The Reverend states the implication of his silence.) Then, in your heart, it was murder, George.
Hannah: God bless you, my boy. I'd forgive him if I failed him.

In the final scene, Angela, wearing black (with a white collar), loyally and faithfully visits him in prison just before his scheduled execution in the electric chair - she still clings to her deep love for him. The condemned George confesses to himself and to his beloved that he is existentially responsible for his pregnant girlfriend's death:

Angela: I came to see you. I thought lots about you, George - all the time. I went away to school to learn. I don't think I learned very much. I love you, George. I wanted you to know that. Well, I-I guess there's nothing more to say.
George: I know something now that I didn't know before. I am guilty of a lot of things, most of what they say of me.
Angela: All the same, I'll go on loving you for as long as I live.
George: Love me for the time I have left. Then, forget me. (They kiss one last time.)
Angela: Goodbye, George. (She half-turns away and then looks back) Seems like we always spend the best part of our time just saying goodbye.

At 5 o'clock, after the Reverend has read a final biblical benediction, George is led to his execution past other death row cells - prisoners bid him goodbye:

So long, kid. Hope you find a better world than this. Goodbye, George. Be seeing you.

But an emotionally-paralyzed George makes no reply - he takes to his death the superimposed image of dark-haired Angela kissing him.