Mannering attends the funeral of Jim Carey, a former army colleague. After receiving a message that Carey is still alive, Mannering agrees to go undercover for Templeton-Green. An elaborate plan to steal a $ 1 m jewel is bad enough but becomes worse when Cordelia is used as a hostage to ensure that the Baron cooperates with Carey.

When Mannering gets a message to buy The Four Horsemen, he travels to Khakania, a country gripped in civil war. The Horseman are a famous statue worth over $1m. The money from the statue will help fund the rebel cause. The Baron tries to flee the country with the rebel leader's daughter and statue but is hounded by the secret police who are always one step ahead of him.

Mannering is asked by an eccentric millionaire to witness him purchase The Legions of Ammrak, a golden necklace that contains seven perfectly matched black pearls. The Baron identifies that they are genuine but David Marlowe notices that the seller, King Ibrahim, is wearing the wrong school tie. When Mannering realises that he's being duped, he has to recover both the money and the necklace.

The sale of a 5000 year old Samurai sword gives the Baron trouble. When the seller, Asano, bumps into an old enemy, Norman Sterling, at Mannering's apartment, Sterling promises to avenge the treatment of him and his brother in a Japanese POW camp. After Asano is murdered, the Baron has to protect Sterling from Asano's loyal servant is out for revenge.