In Somebody Owes Me Money (1969, reprinted 2008), Mr. Westlake shifts gears and writes a snappy comedy. Cab driver Chet Conway loves to play the horses, and when a mysterious fare gives him a tip for a tip, Chet puts his last remaining credit down with his bookie. Purple Pecunia (sic) gallops to a win and Chet dashes to pick up his cash... only to find the bloody corpse of Tommy the Bookie.
Poor unlucky/lucky Chet. As he remarks, if he weren't so eloquent, he never would've charmed the passenger. And if he had never charmed the passenger, he never would've received the tip and wound up in such a mess. Chet's immediately accused of the murder, then let off. Then, he's promptly kidnapped by gangs - two of them - each of them convinced that Chet is working for the opposition. Finally, Tommy's sister flies to town from Vegas to avenge her brother's death.
Chet just wants his money. Even when things get heated, his motivation is perfectly clear. He has no idea what this is all about - he doesn't actually care. The gangsters and the cops and the adulterers and the Vegas vixens can all do their own thing. Leave him out of it. And, of course, give him his money.
In all fairness to Chet, the Vegas vixen (she's actually a blackjack dealer), Abigail, gives him a new motivation. Abi (like Chet/Chester, she insists on the diminutive) is determined to play private investigator and drags the mostly-unwilling Chet along for the ride. While she stirs and schemes, Chet patiently drives her from place to place, noshing on danishes, bemoaning his empty wallet and sneaking peeks at his pretty passenger. Their repartee is terrific. Abi's no sidekick or second-wheel, she's the driving (no pun intended) force of their partnership and the two develop a genuine fondness for one another that's a joy to read.
In fact, from start to finish, Somebody Owes Me Money is a pleasure. Chet's so-called "eloquence" is really a sort of blinkered chutzpah that makes him as unnaturally fearless as any hard-boiled PI. Even when the bullets start flying, Chet never really feels like he's in danger. This is all a silly mistake and if someone would just give him his money, it will all go away. My favorite scene is when Chet (recovering from a shot that grazed him) is visited, consecutively, by every major player in the book, resulting in a series of Nero Wolfe jokes. Eventually, all the mobster rivals show up at the same time to much hullaballoo. Chet can't be bothered to deal with them all, so while the rivals face off in the living room, he strolls into the kitchen and calmly makes a sandwich.
Mr. Westlake doesn't cheat on the mystery aspect either. The solution was a sneaky one, but the clues are there to make it solvable. The problem is, Chet and Abi are so engaging that they maks it hard to play detective. Still, the cheerful duo bounce from one suspect to another, eliminating possibilities and eventually concluding in a high-stakes card game with the Whoddunit (something I think Nero Wolfe would appreciate).