Ken Franklin (Jack Cassidy) is one-half of a mystery writing team, but partner Jim Ferris (Martin Milner) wants to go solo, exposing the fact that Ferris did all the actual writing, and thus leave the high-living Franklin without his cash cow. However, the pair have an insurance policy on which Franklin can collect if Ferris dies during the partnership. Franklin makes it look like Ferris was investigating gangsters. He tricks Ferris into taking a trip to Franklin's remote cabin two hours away. They stop at a general store, where, as Franklin makes a phone call to Ferris's wife (Rosemary Forsyth) to establish an alibi, the owner Lilly La Sanka (Barbara Colby)---obviously smitten with Franklin---peers outside to see whom Franklin brought with him and sees Ferris in the passenger seat of the car. At the cabin, Franklin convinces Ferris to call his wife and tell her he's working late at the office. During the phone call, Franklin shoots Ferris. He drives two hours back to his house with his dead partner in the trunk, dumping the corpse on his own lawn.

La Sanka tracks Franklin to Los Angeles when he is out on a date and loudly approaches him, making it clear that she knows Franklin had killed Ferris, forcing him to cancel his date. He takes her the $15,000 she wants for her silence, feigning interest in her. The two have an intimate dinner in the back of her store, then he bludgeons her and puts her body in a boat which he capsizes to make her death appear accidental.

Final clue/twist: After hearing that Ferris habitually wrote down ideas for his mystery novels on whatever paper was handy, Columbo searches his office and house and finds a note with the fake-phone-call alibi scheme. He confronts Franklin with it, and Franklin confesses. Upon his arrest, Franklin makes a startling comment: the alibi idea was in fact his, the only good one he ever had.

Jack Cassidy played the murderer in three Columbo episodes: this one, episode 22 'Publish or Perish' (Season 3), and episode 36 'Now You See Him' (Season 5).

Carl Brimmer (Robert Culp), the very tough, hard-nosed head of a private detective agency, with unfortunate and fateful anger issues, is hired by Arthur Kennicut (Ray Milland), a powerful publishing magnate who suspects his wife, Lenore (Pat Crowley), of infidelity. Although Brimmer indeed finds evidence of her being unfaithful, instead of reporting this fact to his client, he attempts to blackmail Lenore into obtaining business and political secrets from her husband. She refuses and tells him she will expose his plot to her husband, at which point Brimmer accidentally kills her in a fit of rage. He dumps her body at a scrapyard and later joins the investigation into Lenore's death with Columbo. Brimmer secretly starts to divert suspicion away from himself and even offers Columbo a job.

Final clue/twist: Columbo becomes suspicious when he realizes a cut on the victim's face matches Brimmer's ring. He disables Brimmer's car, causing the vehicle to be garaged for repair. He has Lenore's body exhumed, then claims that one of her contact lenses was not with the body and is missing. He tells Brimmer the lens must be either at the crime scene or in the car the murderer used to transport the body. After searching for it in his home, Brimmer goes to the garage after-hours and searches for it in the trunk of his car. He finds a contact lens, but is caught by Columbo, with Kennicut in tow. When Brimmer tries to throw the lens away the police stop him, and he confesses. After Brimmer is led away Columbo admits to Kennicut he had arranged everything, and that there never was a missing contact lens.

Robert Culp played the murderer in three Columbo episodes: this one, episode 12 ('The Most Crucial Game'), and episode 21 ('Double Exposure'). He also appeared (as the father of the murderer) in 'Columbo Goes to College'.

Notes: This episode won an Emmy for writing and is known for the 'glasses effect' after Brimmer kills Lenore, in which both lenses of Brimmer's glasses simultaneously show different images on-screen of him cleaning the scene of the crime.

Major General Martin Hollister (Eddie Albert), a retired Marine Corps war hero, learns he is being investigated for embezzling military funds, then shoots his skittish accomplice, Col. Dutton (John Kerr). The act is partially witnessed by Helen Stewart (Suzanne Pleshette), who was in a passing boat. She is wooed by Hollister into doubting her own story. Noted Canadian actress Kate Reid plays Helen's disbelieving mother, who is favorably impressed by the distinguished Hollister.

Art critic Dale Kingston (Ross Martin) murders his uncle and tries to frame his aunt (Kim Hunter) to inherit his uncle's very valuable art collection. He later murders his lover and accomplice in the crime, the gullible art student, Tracy.

Final clue/twist: Kingston hides the paintings that he stole after the murder in his aunt's house to frame her, then arranges for the police to find them. Columbo, arriving late on the scene, accuses Kingston of the murder and says he can prove it with fingerprints. Kingston replies that his fingerprints being all over the paintings prove nothing. Columbo retorts that it his own fingerprints that prove the case, from when he touched the paintings early in the investigation, when he visited Kingston in his home. Shaken, Kingston insists that Columbo must have touched the paintings moments ago, to frame him. Columbo takes his hands out of his pockets to show that he has been wearing gloves the whole time.

Beth Chadwick (Susan Clark) murders her domineering older brother, Bryce (Richard Anderson), after he attempts to break up her relationship with one of his executives, Peter Hamilton (played by Leslie Nielsen), a man he thinks is only interested in Beth for ulterior motives. His mailing a letter threatening to terminate Peter's employment if he didn't break things off with Beth causes her to reach the tipping point and to act to gain control of her own life and, it turns out, the family business (as there are no other siblings).

Complications in Beth's plan contribute to Columbo's suspicions. Beth had planned to claim the shooting was an accident. She removed his house key from his key chain thinking it would require him, late at night, to try to enter the house via her bedroom. However, Bryce had a spare key which he had hidden under a flowerpot thus entering the house without ado. She improvises as best she can but her story will ultimately be undermined as a result of this turn of events. Meanwhile, her true personality emerges, showing a very different side than that shown earlier, before the murder.

Final clue/twist: When Columbo re-reads the testimony of Peter Hamilton, who had driven to the house after receiving the letter from Bryce, he notices that Hamilton climbed over the gates and heard the gunshots before the alarm went off, not after. The detail is enough to undo her entire story. Columbo tells Beth that Hamilton won’t like doing it, but he will testify to what he knows.

Roger Stanford (Roddy McDowall) is a chemist whose uncle, David (James Gregory), has taken over a business that his parents built and his aunt (Ida Lupino) controls. David plans to sell the business to a conglomerate, and uses dirty tricks to get Roger to go along. Roger murders his uncle with a booby trapped box of cigars rigged to explode as he drives through the mountains with his chauffeur. William Windom guest stars as Everett Logan, the next-in-line vice president who Roger discredits as part of the offshoot of the murder, so Roger can take over the company. Anne Francis plays David's secretary, who is romantically involved with Roger. Lawrence Cook plays David's chauffeur and right hand man.

Elliot Markham (Patrick O'Neal) is an architect with a vision for a city of the future, and a penchant for classical music. His latest project is being bankrolled by the young wife of Beau Williamson (Forrest Tucker), a wealthy industrialist who has been away on a lengthy overseas business trip. When Williamson returns and finds out how his money is being spent, he is furious, and intends to cut off the funds. Markham decides that the only way he can continue his work is to eliminate Williamson. Simply killing him, however, poses a problem, because his money reverts to a trust fund when he dies. Markham comes up with a clever plan to conceal the body and make it appear as if Beau has gone on another long foreign trip. With Pamela Austin and Janis Paige as the wives, present and past, in Williamson's life.

Final clue/twist: Markham repeatedly goads Columbo into excavating a building site to search for Williamson’s body, until Columbo finally does so. It yields nothing. Later that night Markham returns to that site with the body, assuming no-one would ever look there again. However Columbo has known what Markham has been up to all along, he emerges from the shadows with other policemen and arrests Markham. Columbo reveals that he knew something had happened to Williamson when he checked his car and found the radio turned to a classical music station, something odd for Williamson, who only listened to country music.

John Fiedler portrays Williamson's doctor.