Although the Project Quantum Leap isn't ready yet, Sam Beckett doesn't listen to supercomputer Ziggy, hops into the Accelerator and leaps. As Tom Stratton, an Air Force test pilot about to attempt a dangerous flight. Sam finds his memory Swiss cheesed, with only enough left to know that he is not where or when he belongs. According to Sam's friend and partner Al, who appears to him as a hologram nobody else can see, Al explains that the Project has gone awry and in order to leap out of the pilot's body, Sam must successfully fly the X-2 to Mach 3, which according to historical records, ended in a fatal crash.

As Tom Stratton, Sam comforts his (Tom's) wife and prevents her from having a premature birth. This is what he was sent to do, allowing him to leap home (he hopes). But instead of leaping home, he leaps into Tim Fox, a minor league baseball player in Texas at the end of the 1968 season, in the middle of a game, where he must make the winning play in order to leap further. Aided by errors, Tim Fox, after a dropped third strike on a wild pitch, rounds the bases for the winning score, and Sam leaps into Dr. Gerald Bryant as a college professor in the middle of a class.

At a small Ohio college, Sam Beckett is a literature professor who must discourage the amorous advances of a student and finds the woman who left him at the altar. Sam hopes that resolving her conflicts with her father will prevent her from deserting him.

Sam leaps into a boxer that is owned by a convent of nuns who need him to win a boxing match to finance their new chapel.

Sam finds himself as a veterinarian who has to compete as a cowboy to win the heart of a cowgirl heiress.

Sam leaps into a mafia hit-man who may not live long since he is romancing the godfather's girlfriend. Also an attempt to bring Sam home causes the 1965 east coast blackout.

As the black chauffeur of an elderly southern woman, Sam must overcome prejudice to prevent the death of a black woman.

Sam leaps into the body of a gawky teenager to keep the boy's older sister from marrying an abusive alcoholic. Taking advice from Al, Sam hopes to reveal the young man's true nature by challenging him to a drag race.

Sam, in the body of a Bogie-like shamus, teams up with a 'neat kid' to find the hit man who killed his partner.

Sam must save himself, while on his honeymoon, from his new bride's ex-husband. Also, Congress wants Sam to change history by stopping the U2 flight that was shot down over Russia in 1960.

Sam has to save his host's younger brother from his obsessed father who wants him to go into the family business as a movie stuntman.

As a returning sailor Sam brings home a Japanese wife and must battle the prejudice of his hometown and his own mother.

For his first leap into a woman, Sam is a gorgeous secretary. He must deal with the sexual harassment of his boss and the attempted suicide of his roommate.

As a blind concert pianist, Sam must save his girlfriend from a serial killer despite the interference of her overbearing mother.

Sam is a radio DJ and has to help bring Rock and Roll to Peoria.

Sam leaps into a rabbi to prevent his host's sister-in-law from falling for a sleazy author.

Sam leaps into a young intellectually disabled man and has to keep him out of an institution.

Sam must defend a young black woman charged with murdering the son of a powerful Southern political figure.

Sam must save an alcoholic actor from a fall during a performance of "Man of LaMancha." His old piano teacher is also present and finds Sam's host very attractive.

Sam must save a young woman who drowns while insisting that she is hearing the calls of her dead husband.

Finding himself the king of an "Animal House" fraternity, Sam must win the confidence of a beautiful female activist and prevent the bombing of a school building.

After leaping into a single mother, Sam must prevent the 15-year-old son of his host from disappearing. Al and Sam also find out that very young children can see them as they really are.

Sam must prevent a fellow high school football player from throwing the championship game and losing his scholarship.

As an FBI agent Sam has to protect a female witness when the people after her seem to know his every step.

As an American Indian, Sam escapes from jail to get his grandfather back to the reservation so he can die at home.

Sam leaps into a coroner who must play detective and prove that a female victim was murdered.

Sam leaps into an old pool playing acquaintance of Al's and must win a pool game so that his granddaughter doesn't lose her bar.

Sam must overcome his fear of heights when he leaps into a trapeze artist whose sister dies doing a stunt without a net.

Sam is involved with the kidnapping of a baby while crossing Texas with his stripper accomplice.

Aboard the RMS Queen Mary, Sam must prevent the marriage of his host's ex-wife.

Al tells Sam that he has to convince a Navy nurse that her MIA husband is still alive, but Sam keeps getting signals that he has another mission.

Sam leaps into himself as a 16-year-old boy to help his high school basketball team win the championship. He also tries to help the other members of his family including his father who died from smoking, his brother who was killed in Vietnam and his sister who married an abusive alcoholic.

Still involved in his brother Tom's life, Sam leaps into Vietnam to either save his brother or ensure the success of the team's mission.

As a priest, Sam must save another priest from alcoholism and prevent a murder.

Sam leaps into a fashion photographer and must save a model from a drug dependency due to an ambitious agent.

Everything goes wrong when Sam leaps into a Gothic horror novelist on Halloween.

While entered in the "Miss Deep South" beauty pageant, Sam must prevent a fellow contestant from posing for some nude photos and make sure his host comes in third in the contest.

As a black medical student during the 1965 Watts riots, Sam must save his white fiancée.

Sam leaps into a magician who must keep custody of his daughter and save her from an accidental death.

As a member of a motorcycle gang Sam has to keep a young woman from going on the road.

Sam and Al scare the Dickens out of a rich Scrooge character who wants to tear down a mission and build a high rise.

Sam must put up with a bratty older sister and keep the family together while saving his mother who disappears.

Sam leaps into a very pregnant teenager and must convince her father to help her keep the baby.

As the sidekick on the 1950s children's science fiction series "Time Patrol", Sam must prevent the death of the star of the show.

As a male stripper, Sam must save a deaf girl from a life of prostitution and get her an audition with a professional dance company.

Sam is a piano player who is on the run from a killer with an ex-girlfriend.

Sam leaps into the proprietor of a New Orleans brothel and has to prevent the death of a girl who really doesn't belong there.

Sam becomes a member of a rock band who is stabbed to death after a concert by one of a long list of suspects.

Sam leaps into a bounty hunter who is handcuffed to a female fugitive who will do anything to escape from him.

Sam leaps into a death row convict moments before his execution. A last minute stay of execution order gives him 48 hours to determine his innocence in a leap with an unclear mission.

Sam leaps into a wrestler who must convince his partner-brother to quit due to a heart problem.

Sam must deal with the panic associated with the Cuban Missile Crisis as a Florida fallout shelter salesman.

Sam leaps into a patient at a Mental Hospital and undergoes electroshock therapy. The treatment causes Sam to act like other people he's been. It also weakens his link to Al. Al must find a way to get his friend back to normal, and figure a way to carry out Sam's mission.

Sam and Al have switched places. Now Sam is the hologram, and Al is the leaper. Al must reunite a returning WWII veteran with the woman he left due to the war. Sam and Al must figure a way to communicate with the future, because Al has the comm device, and Sam has no way to contact Ziggy.

Sam is a minor league baseball pitcher who has plenty of female admirers and a porcine team mascot to watch out for.

As a deputy sheriff, Sam must prevent a murder as Hurricane Camile hits the Mississippi gulf coast.

Having leaped into a member of the Ku Klux Klan, Sam must save the life of a civil rights worker.

Sam leaps into a hair dresser to prevent the death of a murder witness.

Sam leaps into a rape victim and must testify against the attacker who is an outstanding member of the community.

Sam leaps into a chimpanzee used in the early days of the space program and has to save a fellow chimp from testing that will result in his death.

Sam leaps into a detective that is working on a gruesome murder and must deal with flashbacks from the mind of his leapee.

Sam leaps into a rainmaker who returns to his drought-stricken hometown and has to keep his family together.

Sam must save a fellow convict from a chain gang in 1956.

Sam finds himself as a young man involved with an older woman who has singing aspirations and needs a confidence boost from Sam.

At a Naval college, Sam must prevent a gay fellow classmate from being killed by a gang of other students.

As a television reporter Sam protects a psychic, who can tell who Sam Beckett really is, from a serial killer.

Sam leaps into an elderly man who likes his whiskey and tells tall tales. His former partner and fellow gunfighter shows up wanting recognition and revenge.

Singing in a 1960s black girl band, Sam must save one member from an unscrupulous nightclub owner.

Flying through the Bermuda Triangle strange things occur as Sam must get a sick passenger to a doctor.

In the role of a "Geraldo" type journalist, Sam and an asthmatic woman try and uncover the truth about what is going on at a local chemical plant.

As a New York City cab driver, Sam has to win a contest to get his own taxi medallion. Sam also has the help of a woman named Angelita who knows about Sam and claims to be an angel.

Sam is kidnapped by an obsessed soap opera fan.

At an archaeological dig in Egypt Sam has to deal with an approaching sandstorm and a 3000 year old curse.

As part of a Catskills comedy act trio, Sam has to convince the other two members that they are in love while saving one of them from the mob.

While trying to save a married woman, Sam changes history and Al is sent to the gas chamber giving Sam a new observer.

Sam's leap takes a dramatic turn when he begins leaping randomly throughout the life of Lee Harvey Oswald, accused assassin of President John F. Kennedy. Matters are complicated further when Sam's mind becomes tangled with Oswald's.

As the date for Dallas draws nearer, Oswald's personality is getting harder to control. Al is finding it harder to connect with Sam. Is Sam supposed to save the President, or unearth the conspiracy?

Sam is a Greek sailor lost at sea with a bratty debutante, who was on what was supposed to be a honeymoon cruise.

As a double amputee Vietnam veteran, Sam must prevent the suicide of a fellow hospital patient.

Sam leaps into a hostage situation as a fugitive killer. The real killer breaks out of the Project facility and is on the run in 1999.

Sam leaps into a 79-year-old man who claims to have seen UFOs to save him from being committed and his grandson from dying of a drug overdose.

Sam discovers another set of leapers who are messing with history.

Sam is a small-town sheriff whose young daughter has a suspicious connection to a mysterious death.

Sam leaps back into the life of Abigail Fuller, this time as her fiancé, who must save her when she again is suspected of a killing.

Sam leaps into Abigail Fuller's attorney in a murder trial with personal implications.

Sam finds himself back in his hometown at Christmas time to save the farm of a neighbor.

Sam must decide between families when he leaps into a salesman with two wives.

Leaping into the middle of the woman's liberation movement Sam must prevent the death of a young lady at a sit-in and convince her father to live with a liberated daughter.

Sam leaps into the sex therapist Dr. Ruth Westheimer, plays matchmaker for a couple on the staff of her radio show and helps a woman deal with sexual harassment.

Sam leaps into an English castle where the occupants practice vampire rituals. He must save the young wife of the castle owner.

Sam leaps into a college fraternity and again meets Alia from the Evil Leaper Project.

After saving Alia from the Evil Leaper Project, Sam is trapped with her in a women's prison with the evil observer Zoey in charge as the prison warden.

As the chauffeur of Marilyn Monroe, Sam must save her life and help her to make one final film, Los inadaptados (1961).

As a Vietnam veteran, Sam is mistaken for Bigfoot in rural Washington state.

Sam Beckett leaps into his great-grandfather during the Civil War and must not interfere with his great-grandparents meeting nor get captured behind Confederate lines.

While impersonating the King, Elvis Presley, Sam must save a Memphis Belle from a bad marriage.

Sam leaps into a bar with a bartender that's more than he appears. When Sam looks into a mirror, he sees his own reflection. In the future, they realize that Sam has leaped into himself, they search history for Sam. Sam learns more about Quantum Leap, and who's responsible for his leaps. Before he takes his next leap, he realizes he must correct something that could affect his personal history.

Sam must defend a young black woman charged with murdering the son of a powerful Southern political figure.

Sam finds himself as a young man involved with an older woman who has singing aspirations and needs a confidence boost from Sam.

Sam leaps into the body of a gawky teenager to keep the boy's older sister from marrying an abusive alcoholic. Taking advice from Al, Sam hopes to reveal the young man's true nature by challenging him to a drag race.

In the role of a "Geraldo" type journalist, Sam and an asthmatic woman try and uncover the truth about what is going on at a local chemical plant.

Sam is kidnapped by an obsessed soap opera fan.

Sam leaps into himself as a 16-year-old boy to help his high school basketball team win the championship. He also tries to help the other members of his family including his father who died from smoking, his brother who was killed in Vietnam and his sister who married an abusive alcoholic.

Leaping into the middle of the woman's liberation movement Sam must prevent the death of a young lady at a sit-in and convince her father to live with a liberated daughter.

Sam leaps into a coroner who must play detective and prove that a female victim was murdered.

Sam leaps into a chimpanzee used in the early days of the space program and has to save a fellow chimp from testing that will result in his death.

As a television reporter Sam protects a psychic, who can tell who Sam Beckett really is, from a serial killer.