Kidnappers abduct a young woman, believing her to be the daughter of a millionaire. In reality, she's the daughter of a middle-class couple who had been driving the car of the intended victim. Erskine and Colby lead the FBI's investigation of the case. But the daughters of the victim don't have the means to raise the ransom. Meanwhile, the rich father of the intended kidnap victim doesn't want to provide the ransom because it would violate the principles he has lived with all his life.
An attempt to steal a top secret formula at Millard Industries in Dallas fails when only half the formula can be taken before a security guard enters the company's computer room. The CEO of the company summons the FBI and Erskine goes undercover at the firm. The son-in-law of the founder of Millard has been seduced by a Soviet Bloc agent. The executive is unaware of the Communist affiliation of his mistress. A chemist at the company has been set up as a stalking horse so the executive can continue and steal the rest of the formula.
A $1 million painting is stolen from a museum in Kansas City, Missouri. The thieves initially plan to sell it to a collector in Europe. But when that buyer dies in an accident, they instead seek to sell it back to the museum. Inspector Erskine poses an art expert who the thieves will call upon to confirm the painting is genuine. But what Erskine doesn't know is that he arrested one of the thieves, who has been working in the museum as a volunteer, eight years earlier.
Three men attempt to kidnap a doctor vacationing in the mountains of Washington state. The doctor falls down a steep hill side. One of the three kidnappers is tracking the doctor while the other two proceed with plans to extort $200,000 from his wife. The FBI gets a break when one of those two is arrested for another crime. Erskine and Colby try to pick up the trail of the doctor. Meanwhile, the physician is playing a desperate game of cat and mouse with the man tracking him.
A crusading newspaper columnist narrowly avoids death in a murder attempt at his home. The van used by his would-be killers was stolen and crosses state lines, bringing the FBI into the case. Erskine and Colby lead the bureau's investigation. But there's more to the case that seems apparent. The columnist utilizes a snitch who's playing both sides. What's more, the person behind the contract on the columnist may be one of his friends.
Erskine goes undercover to infiltrate an Eastern Bloc spy ring operating in the U.S. The inspector has to take on the assignment despite not knowing every detail about the man whose identity he has assumed. The FBI man also will be forced to improvise after a major shakeup has caused the liquidation of the Eastern Bloc official responsible for the spy ring.
A U.S. Marine is stabbed and seriously wounded, causing the FBI to investigate. Erskine and Colby end up on the trail of a gang who steal firearms from a U.S. military facility. The gang intends to sell the weapons to a group of extremists.
Erskine and Colby are assigned to a case involving the theft of valuable jewels. The FBI men will soon need to unravel a web of deceit, involving a father (who a veneer of being a respectable businessman), his daughter and a thief. The father, seeking to protect his reputation, puts his daughter into peril by hiring a hit man to kill the thief. The question is whether the FBI men can crack the case in time.
Jerome Williams, an AWOL U.S. Army private, robs a bank. During his getaway, Williams takes in a young woman hitchhiker. It's only when they approach a roadblock that she realizes Williams is a fugitive. Williams isn't a hardened criminal; he robbed the bank, in part to gain attention. Erskine and Colby lead the FBI manhunt for Williams, who injures two men as the chase continues. On top of everything else, Williams gets the attention of a gang of bikers. Williams has taken jewelry from a businessman worth $20,000.
A robbery of an armored car in Michigan goes badly. But one man, the getaway driver, escapes. The robbers weren't aware of how large a target was involved. The armored car had $500,000. The driver tries to cut a deal with the mastermind of the holdup but is double crossed. The driver, though, manages to escape with all the money. Now, the FBI -- led by Erskine and Colby -- is after the thief along with the criminal who planned the robbery.
A New York-based gambling syndicate has its hooks deep into a mens college basketball team from Jefferson City, Kentucky. One of the team's players is injured when the team doesn't win enough to the syndicate's liking. Erskine and Colby lead the FBI's investigation into a potential point-shaving scandal. Meanwhile, the team now is ready to play for the college championship and the syndicate doesn't want to take any chances. When one player refuses a bribe, the gambling syndicate kidnaps his sister to ensure the final score results in a big payoff.
In Denver, almost $1 million is stolen when three thieves tunnel into a bank vault from an empty building next door that they've rented. Erskine and Colby lead the FBI's investigation. The ringleader, who spent all of an inheritance, plotted the crime so he could win back the woman he loves. The weaknesses of the three conspirators will eventually provide the clues the FBI men need to solve the case.
In San Francisco, professional football quarter back Paul Talbot is the target of an extortion scheme. The extortionist breaks into Talbot's home to demonstrate he's capable of harming the athlete's family. The FBI, under the supervision of Erskine and Colby, keeps watch as Talbot drops off the extortion money. But Talbot interrupts the bureau's surveillance, punching out the accomplice of the extortionist. The criminal vows to kill Talbot while he's playing in the championship game.
A young woman is kidnapped in Colorado. Her adoptive parents, however, are not wealthy so there isn't an obvious motive for the FBI in its investigation. As Erskine and Colby's investigation proceeds, it emerges the woman's biological father was involved in the theft of $400,000. The kidnap victim was only eight years old at the time. The trauma involved caused her to shut out memories of the incident. The kidnappers bring her to a national forest in Utah, trying to make her remember where the money is hidden.
"Doc" Lacy, a legendary criminal, has been incarcerated for 27 years. A gang arranges for Lacy to escape from a Louisiana prison farm. The gang wants Lacy to plot a robbery of a million-dollar Army payroll in Washington state. The infirm Lacy, who has a weak heart, also wants to see his estranged son and wife before the robbery. Erskine and Colby lead the FBI's manhunt. Despite his advancing years, Lacy is quite dangerous who's not afraid to kill if he has to do so.
A con man poses as a psychic to bilk rich people. One of his victims spots the criminal pocketing jewels and realizes he has been had. But the criminal gets away and crosses state lines, bringing the FBI into the case. As Erskine and Colby begin their investigation, the con man has a new target: one of the richest women in Connecticut, who lost a son a year earlier.
The youngest son of a millionaire rancher is kidnapped. As Erskine's investigation unfolds, it becomes apparent there's more to the case than appears. The truth evokes Cain and Abel and involves multiple double crosses. With time running out, Erskine races to solve the case.
In Louisville, Kentucky, a team of four men robs an amusement park of more than $1.8 million. But the mastermind of the plot double crosses the others and gets away with all the money. Now, the three robbers and the FBI are after the same man. Erskine and Colby follow a trail from Louisville to Cincinnati to St. Louis as the investigation unfolds. Meanwhile, the man who planned the robbery returns to his home in San Diego, his wife unaware of the double life her husband has been living. The bureau apprehends one of the robbers in St. Louis, the first major break in ...
One member of a gang that robbed more than $1.8 million has been arrested in St. Louis. Under questioning from Erskine and Colby, he reveals the names of two other members of the gang but says he doesn't know the identity of the mastermind behind the holdup. The gang only knew him as "the salesman." The FBI apprehends another gang member in St. Louis. Meanwhile, the last member has figured out "the salesman" is in San Diego. The FBI, under Erskine's direction, also now seeks the mastermind in San Diego. The question is who will reach "the salesman" first.
In Boston, a Communist spy ring is after top secret plans of a defense contractor. A scientist employed by the company has stolen part of the plans for $5,000. But he attempts to blackmail the spy ring's leader for another $5,000 to supply the key plans of the project. Luther Shawn, the ring leader, calls his bluff and has his Rottweiler attack, nearly killing the scientist. The spy ring's No. 2 man now attempts to seduce a lonely administrative assistant who has access to the plans. The FBI, led by Erskine and Colby, is assigned to the case after messages from a ...
At a boarding school in Arizona, the son of a rich businessman in Denver has become friends with two other boys. But the boys, member of the school's cross country team, imprison the businessman's son in an abandoned underground chamber that had been used to store explosives. Erskine and Colby head up the FBI's investigation. The Denver businessman, ignoring the bureau's advice, decides to pay the $25,000 ransom. The FBI begins to put the pieces together. But the underground chamber is about to be buried as part of a construction project. The question is whether the ...
Thieves execute a daring jewel robbery in downtown St. Louis and flee across the state line to Illinois. There, a helicopter awaits to take them to safety. This brings the FBI into the case, with Erskine and Colby heading up the investigation. The thieves turn the stole jewels over to a fence. The helicopter pilot isn't satisfied with his share and takes more. The thieves have another job lined up and need a new pilot. They select a man who's down on his luck and growing desperate.
An employee of the Bureau of Indian Affairs is in a coma after an attack at a hard-luck mine called Superstition Rock. Because a federal employee is involved, the FBI is called into the case immediately. There have been a series of incidents at the mine that have spooked the American Indian employees. They believe the incidents indicate the mine is near an Indian burial ground. While Erskine supervises the bureau's investigation, Colby goes undercover as an ex-con who is now a new mine employee. The investigation turns up a conspiracy intended to force a sale of the ...
A Communist sleeper agent in New York has just been activated. The sleeper is known to the FBI and is being watched. But shortly after being activated, the agent has a heart attack. Erskine goes undercover, assuming the man's identity. His target is an operative known as Minerva, who is operating out of Pittsburgh. But the assignment has more than the normal risk. There's a power struggle under way among the spy ring. Minerva has recorded a set of tapes that he believes will be his "insurance policy." For Erskine and the bureau, those tapes are an opportunity to gain ...
The mob makes a move to infiltrate fisherman fleets on the U.S. West Coast. Erskine spearheads the FBI's investigation and Special Agent Colby goes undercover as a fisherman. The mob has gotten to a respected leader among the fishermen -- getting him to accept a loan before canceling it. Colby's life will be imperiled as the bureau's investigation proceeds.
A criminal conducts a bank robbery in Lincoln, Nebraska. The robbery nets $12,000 but is only a preliminary job. The criminal's next job involves robbing a New York City department store. To do that, he'll recruit a team while also romancing a woman he met a few months earlier. Erskine and Colby move across multiple states while on the criminal's trail.