What's so Funny by Donald E. Westlake
The plot of the story revolves around an ex-cop private detective blackmailing Dortmunder into stealing a bejeweled, golden chess set meant for Czar Nicolas II. But it's hidden away in the vault of a bank, and it never comes up for air. The heirs to the chess set are locked in a legal struggle to see who inherits and it's Dortmunder's job to bring the chess set out into the open to have experts check it out, and that's when Dortmunder and crew will pounce.

The blackmail effort is for an elderly retired inventor, Mr. Hemlow, who wants to recover a stolen chess set worth millions that had once been intended for the last czar, but the Russian Revolution countered that option before the chess set was delivered. Hemlow's father and some fellow army and navy personnel sneaked the set out of the USSR during the anti-Soviet battles just after World War I. Their sergeant retrieved the set from his squad after they returned to the U.S. and disappeared with the chess set. Now, Hemlow's granddaughter, an apprentice lawyer who fancies herself an amateur historian, has located the set. Hemlow wants Dortmunder to liberate the valuable prize.

He brings the old gang together and it's a hoot to watch how nervous they all are because of the ex-cop/now detective in the picture. Lots of laugh out loud moments and the usual surprise ending.