What's the worst that could happen? - Donald E Westlake

It started with a ring. A cheap ring. The yellow metal said brass, not gold, and the sparkly bits were certainly not diamonds. But the ring belonged to May's horseplaying uncle, who swore it brought good luck. Dortmunder, who wouldn't kick a little good luck out of bed, puts it to the test when he goes to burglarize Long Island billionaire Max Fairbanks. As luck would have it, Dortmunder is greeted by Fairbanks himself - and a loaded gun - as soon as he strolls through the door. When the cops arrive, the mogul adds insult to injury by claiming that Dortmunder's lucky ring is actually his. Big mistake, big guy. As soon as Dortmunder can give the cops the slip, the world's most single-minded burglar goes after the fat cat with a vengeance and a team of crooks that only he can assemble. And from the get go everything will go Dortmunder's way - everything, that is, except the ring.