The Baron Comes Back — John Creasey

Although John Mannering -- alias the Baron -- had been enjoying his retirement from his ‘Baronial' activities as a jewel thief, he was nonetheless tempted by the offer of the strange little Frenchman who visited him late one night. So tempted, in fact, that he accepts, and resurrects the Baron in return for a superb diamond. In doing so, Mannering is plunged into the search for a famous collection of precious stones smuggled into the country by an organization which, he suspects, is also dealing in human contraband.

But Mannering, having agreed to help the organization, finds himself in a difficult and dangerous situation; as John Mannering, he is obliged to do all he can to help his old friend Superintendent Bristow, but, as the Baron, he finds himself on the run from the police once more…