Baretta comes to suspect that his close friend, a music store owner, may not only be a drug dealer, but may be unknowingly selling heroin so pure that it is killing his customers.

Baretta has to go on the run to clear his name after he is framed for the murder of a gun dealer he was investigating, who was selling weapons to teenagers.

Baretta must use his wits to survive after he and a runaway girl he apprehended unwittingly get into a police car being driven by a couple of holdup men disguised as cops.

When a conventioneer is murdered, Baretta finds that the only witness is a busboy who doesn't want to get involved, but the real murderer is after the man too.

To find an arsonist, Baretta seeks the help of a former investigator who retired after suffering both physical and psychological damage in a fire.

While Baretta is investigating a series of waterfront killings, his cover becomes in danger of being blown by a waitress who knows him and thinks he is responsible for the death of her boyfriend.

Persuaded by his grandson to reopen the case of a retired cop supposedly killed in a fall, Baretta discovers a judge on the take.

To infiltrate a gang of jewel robbers, Baretta seeks the help of a former expert safecracker he once sent to prison.

When a dying hoodlum entrusts his girlfriend with a detailed record of all his underworld activities, she is sought by both the police and his former cronies seeking to protect themselves.

Baretta doggedly follows a truck driver he suspects of killing the cat burglar who injured his wife, waiting for the man to make a mistake that will reveal his guilt.

Baretta is investigating a mob theft of diamonds belonging to Mr. Nicholas and winds up helping a merchant who is threatened by a new group in the neighborhood called the East Side Benevolent Society, who is forcing all the shop owners to pay money for protection or suffer the consequences.

Baretta must find a nurse's 9-year-old sister, witness to the murder of a blind hot-dog vendor, before the killers do.

When his partner is charged with shooting a suspect in the back, Baretta tries to locate the only witness who can save the man's career, but the real murderers are after him too.

When a plea bargain falls through, Baretta must infiltrate a murderous motorcycle gang to save his informant.

After a crime lord is arrested, Baretta must jeopardize an undercover policewoman to stop an escalating war of succession between gangland factions.

Believing that Baretta pocketed $500,000 in stolen bonds after stopping a robbery, a mobster takes Billy hostage until the money is turned over.

After a young pickpocket is killed, Baretta solicits the help of an expert to infiltrate the gang that operates at an airline terminal.

Baretta risks his life going undercover as a prison inmate to discover why two suspects in a jewelry heist were killed.

Pursuing a gunrunner with spinal meningitis, Baretta becomes infected and has 48 hours to find the man and his cohorts before he has to go into quarantine.

A retarded waitress who sees a narcotics cop commit murder allows herself to be persuaded that another man committed the crime.

When a mother has second thoughts after selling her baby, she helps Baretta infiltrate a group trafficking in black market babies.