When Timmy's old school friend is murdered in France, he learns that the old friend was just not a painter but an intelligence agent at which time Timmy and Marcel decide to go Paris to investigate what appears to be unfinished espionage.
Tony is robbed of a valuable pearl necklace - that he has just stolen from a crooked jeweler - by The Cat. He plans to recoup his loss by getting involved in The Cat's next caper.
Tony buys an entire lot of 22 ships sold by the US Navy, then offers to sell them to a crooked shipping magnate by convincing the man that on one them, $2 million worth of gold bullion is hidden.
In Budapest, an old friend engages Marcel and Timmy to smuggle a intelligence computer. When the friend is murdered, corrupt official forces the pair to do his personal smuggling but the two plot to accomplish the original task.
The rogues get word the President of San Luco has arrived in the US to sell the Stefanini jewels. Miss Harkness explains how the jewels originally belonged to their family and decide to get them back.
In Boston, a friend of Tony's loses his business to a wheeler-dealer named Mannix. Tony schemes to raise the money to buy it back for him by selling Mannix a company he doesn't own.