In The Thief Who Couldn't Sleep (1966), the first book, Tanner takes an avid interest in political causes, primarily the ones existing in the late 1960s when the series first takes place. He is also very good at "coming across money", so when he meets a black-haired woman whose grandmother has fantastic tales of a fortune in European gold hidden under her front porch in a war-torn country, he embarks on a profitable journey. Though only intending to extract five hundred seventy-three pounds of pure gold, he accidentally starts a revolution in Macedonia when his principled support for the rebels' cause is interpreted as a guarantee of American military support. From there, Tanner ends up in a Turkish jail and is hired by a government agency so secret that even the CIA has never heard of them.
In The Canceled Czech (1966), Tanner's new employer may have mistaken him for an informer to one of their dead agents, but that does not stop him from taking over the position and rising to become one of their best agents. As one of their men, he must "cancel" a Czech who was a former Nazi, smuggle twelve female Olympians, one princess, and a defector aboard a Soviet fighter plane to America, end a sexual slavery ring, and rescue a cannibal named Jane from Africa.
In Tanner's Twelve Swingers (1967), during the Cold War, Tanner goes behind the Iron Curtain into Latvia to rescue a friend's girlfriend from communists, but she will not leave without eleven limber teammates, a subversive author, and six-year-old royalty.
In The Scoreless Thai, also known as Two for Tanner (1968), Tanner goes to Thailand to seek a beautiful singer who may also be a jewel thief. Posing as a butterfly hunter, he himself is netted by bandits, makes a deal with a horny young man, gets lost in the malaria-filled jungle, and starts a little war.
In Tanner's Tiger (1968), there are Cold War tensions at the Montreal World's Fair, including a Cuban exhibit, a heap of drugs, Minna, the little girl in line for the Lithuanian throne, the future Queen of England, and a hot woman in a tiger skin.
In Here Comes a Hero also known as Tanner's Virgin (1968), Tanner rescues a woman named Phaedra, who has been abducted by white slavers in the Afghan wilderness. Her honor is at stake, featuring trigger-happy terrorists and a few assassinations.
In Me Tanner, You Jane (1970), Tanner is in Africa where the petty despot of Modonoland has gone missing and taken the state treasury, featuring the CIA, white supremacists, revolutionaries, and a blond jungle bombshell named Sheena.
In Tanner on Ice (1998), while meeting with a double crossing Scandinavian resistance operative, Tanner was incapacitated and cryogenically frozen, though not intended to be brought back. In 1997, his freezing machine was found within a secret chamber of a house being remodeled and repaired with Tanner still inside. Due to new technology, doctors were able to reanimate a perfectly preserved Tanner and he was let loose in then modern day New York City. When he came back home, he found that it was occupied by his adopted daughter, Minna, the rightful heir to the Lithuanian throne, now fully grown. He also finds that he still has a job with his old boss, even though he has been out of it for twenty-five years. His new assignment takes him to former Burma (now called Myanmar) and the deadly Orient, which he has not seen since the events of The Scoreless Thai. To make things even more complicated, he has to bring back an exiled Russian beauty, overcome malaria, and get used to the new world.