As of July 2026, Unsolved Mysteries Season 4 aired in 1991 with 54 episodes — streaming now on Amazon Prime Video. Full episode guide and where to watch below.

Unsolved Mysteries Season 4 poster

← Back to Unsolved Mysteries

Unsolved Mysteries Season 4

1991 54 Episodes Mystery · Drama ⭐ 8/10

Right now you can watch Unsolved Mysteries Season 4 on and — and it earns its twists rather than manufacturing them. A compact run that never overstays its welcome. Its 8/10 TMDB score, built from 149 ratings, reflects a title that consistently delivers. Robert Stack anchors it, but the writing does the real work. Available now — press play and find out why people keep recommending it.

Unsolved Mysteries Season 4 is not trying to be everything to everyone, and that focus is exactly what makes it work. The plotting in Unsolved Mysteries Season 4 is tight enough that the twists feel earned rather than assembled. Season 4 of Unsolved Mysteries includes 54 episodes. It aired from September 1991 to September 1992. This season stars Robert Stack. Robert Stack leads a cast that brings real weight to the material. It was aired in 1991. What makes Unsolved Mysteries Season 4 hold up is that the resolution matters less than how the characters get there. The hit rate here is high enough that skipping ahead never feels like an option.

If you cannot walk away from a good mystery, Unsolved Mysteries Season 4 will keep you hooked. It rewards viewers regardless of what else is in their watch history. Short enough to finish in a weekend, substantial enough to feel satisfying. Robert Stack's performance is the kind that shows up on best-of lists years later. If you have been looking for something to fill the gap left by a recently finished story, this is a reliable answer.

📡 Where to Watch Unsolved Mysteries Season 4

🇦🇺 Australia

Amazon Prime Video

Amazon Prime Video with Ads

🇺🇸 United States

Amazon Prime Video

Peacock Premium

Amazon Prime Video with Ads

Peacock Premium Plus

🇬🇧 United Kingdom

Amazon Prime Video

Amazon Prime Video with Ads

🇨🇦 Canada

Amazon Prime Video

Amazon Prime Video with Ads

🇳🇿 New Zealand

Amazon Prime Video

🎬 Unsolved Mysteries Season 4 — Episode Guide

Beginning a fourth season: U.S. military officers discuss a 1980 sighting of an unidentified flying craft near a U.S. air base in England. Also: the murders of two Texas teens reportedly involved with a cult; a Nashville, Tenn., woman's discovery about her parentage.

New theories in the death of Lincoln assassin John Wilkes Booth; the disappearance of a 65-year-old man with no past; and the search for a convicted child abuser.

Reports: an amnesiac found unconscious in the Las Vegas desert; the grisly murder of a Virginia woman; the controversy surrounding the Shroud Of Turin.

The hunt for a suspected serial killer who's been stalking women in Connecticut since 1981; the search of Florida siblings for their twin brother and sister, who were adopted as infants; the first-time meeting of a father and his 32-year-old daughter.

U.S. intelligence reports suggesting that there were survivors of a spy plane shot down over Laos in 1973; the search for a fugitive con artist who defrauded the elderly out of millions; a West Virginia woman's reunion with her twin sister's four sons.

Reports on suspicions surrounding the disappearance of an Oregon police officer's son; an Indiana man's search for a friend and father figure of 20 years ago; the hunt for a man who reportedly murdered his estranged wife and her co-worker in front of witnesses; the recovery of a Maryland amnesia vic...

Segments include reports of ghostly goings-on at a New Mexico hotel, and hauntings experienced by a couple who moved to a 109 year old Florida mansion last year. Also: the search for a con man who poses as a doctor to steal jewelry, coins and computers.

This special edition focuses on what producers call ""the diabolical mind."" Included: profiles of Adolf Hitler and Saddam Hussein; an interview with a convicted murderer.

Reports on a case of past-life regression; the search for a couple reportedly involved in a Christmastime fraud escapade; a 1985 murder-extortion plot in Denver; the disappearances of Florida convenience-store workers.

A repeat report on crime fighter Eliot Ness's efforts to solve the case of a 1930s Cleveland serial killer. Also: new reports on law enforecement's use of psychics to solve cases; an investigation into the death of a North Dakota woman; and a Maryland amnesia victim.

Included: a woman's search for the police officer who risked his job to free her from an unjust sentence; new evidence in the case of a mother jailed for the death of her son; the hunt for a Fort Pierce, Fla., con-artist team who reportedly committed murder.

UFO sightings over Belgium are discussed by reported witnesses, the police and military personnel. Also: the disappearance of a Michigan company president, charged with embezzlement; questions surrounding a police chief's death.

Reports on the FBI arrest of a fugitive in Commerce City, Colo.; a possible military coverup in the 1989 death of a Marine Corps captain; the search for a Florida church arsonist; the discovery by two women that they are sisters and a report on an impostor.

Reports on the murderous aftermath of Durant, Okla., jail escape by two killers; the suspicious death of a man who squandered an elderly widow's money; two brothers' search for the mother they haven't seen in 42 years; the abduction of a 6-year-old boy.

Reports: a con game using state lottery tickets that took in millions of dollars in New York state alone; the search for a homeless person who may stand to inherit $100,000; a former runaway's search for three of her nine estranged siblings.

Segments on an abusive grandmother who reportedly kidnapped her 2-year old grandson; a convicted murderer who claims he's innocent in his wife's 1983 murder; a fugitive's capture outside Birmingham, Ala; and two Ojibwa sisters from Manitoba who are searching for their estraged sister.

U.S. military officers discuss a 1980 UFO sighting near a U.S. air base in England. Other segments include the murders of two Texas teens reportedly involved with a cult. (Repeat)

Repeat segments on new theories in the death of Lincoln assassin John Wilkes Booth; and the disappearance of a 65-year-old man with no past. Also: viewer tips leading to the arrest of a fugitive child molester.

Reports on the 1988 disappearance of a Washington State student who picked up a hitchhiker and was never seen again; a Georgia man's search for his brother, who he suspects is still alive following a 1990 boating accident; the search for a ""love child"" who stands to inherit $24 million.

Repeat reports on the grisly murder of a Virginia woman; an amnesiac found unconscious in the Las Vegas desert; the controversy surrounding the Shroud of Turin; and the search for the husband of a murdered Rochester, N.Y., woman.

🎭 Cast of Unsolved Mysteries Season 4

Robert Stack

📋 All Seasons of Unsolved Mysteries

Season 1 Season 2 Season 3 Season 5 Season 6 Season 7 Season 8 Season 9

Never Lose Track of Unsolved Mysteries

TV Butler Pro lets you search every streaming service in seconds, tracks what you've watched, and works completely free. No app download needed.

🎩 Try TV Butler Pro Free