Brett's relatives are being killed off one by one, so Brett and Danny decide to find the killer before he gets to Brett.

Brett's family mansion seems to have been restored without his knowledge, and taken over by strangers. To find out why, he pretends to be the actor they have hired to impersonate him, and ends up helping the Prime Minister.

While out camping at Brett's family estate, Danny gets chained to a brief case which he can't get off that contains a bomb.

Danny buys a `handy man's special' cottage in England and discovers that his neighbors are into the occult.

After Brett loses seven days, Danny thinks Brett is acting strange but Brett thinks someone is impersonating him. They both can't be right.

Trying to open a travel business, Danny and Brett encounter a New York hoodlum who needs to be smuggled out of Italy after he killed an Italian gangster.

In order to catch a war criminal, Danny must impersonate the kidnapped Brett, but how will he explain an English Lord with a Brooklyn accent?

When Brett's plan to capture a traitorous British spy by pretending to be him results in his own capture, Danny enlists the aid of one of Brett's relatives to rescue him.

At a London airport, a gang of crooks who are planning a bullion heist mistake Danny for a criminal mastermind when the man's suitcase accidentally ends up in Danny's luggage cart.

Danny and Brett try to help a girl whose ""long lost brother"" has suddenly appeared, cutting her off from her inheritance.

Danny has to go on the run from enemy agents after his gambling winnings at a Brighton casino turn out to be part of a communist plot to pay off spies when they use the right code words.

It seems that everyone including a former Nazi wants a German Eagle statuette, and they think that Danny is the one who has it.

When Danny and Brett find the decade-old dead body of a scientist in a crashed plane in the Scottish Highlands, several women claiming to be his daughter offer them various inducements to part with the formula they found.

Seeking sanctuary with his old friend Brett is a spy who plans to publish his memoirs, which contain the name of every NATO, SEATO, and ANZUS agent.

A retired judge who regrets those criminals he had to let get away arranges for Brett and Danny to meet, and then gets them arrested so that they have the choice of either helping him out in his fight against crime or staying in jail. Their first assignment is to locate an heiress by her heart-shaped birthmark.

When the Judge tricks Brett and Danny into identifying a dead woman found floating in the waters of the French Riviera, they end up investigating an international stock swindle.

Danny runs into political intrigue when he discovers the dead body of a reporter, then can't find it until it turns up in a car crash hours later.

After Danny is accused of kidnapping his blind date, a rich man's spoiled daughter, Brett and Danny decide to help rescue her from the real kidnappers but have problems keeping her rescued.

Brett wakes up one morning and discovers that he got married the night before.

To retain the family jewels, an elderly Russian duchess must present proof of her marriage into the Russian Royal Family, which she says she can do with the help of a journal kept by one of Brett's uncles.

Brett and Danny both end up wooing an heiress after they are asked to break up a romance between a her and a gigolo who is courting her.

Brett resumes race car driving, only to become the target of someone who is willing to kill him in order to make him stop.

Danny and Brett must discover whether or not Gold Napoleon coins are the originals, or replicas as a coin dealer claims them to be.

An childhood friend of Danny's from the Bronx turns out to be a hit man hired to kill an American labor leader on holiday at the Cannes Film Festival.