The House in Turk Street 4

This and "The Girl with Silver Eyes" are effectively one long story in the same way that "The Big Knockover" and "$106,000 Blood Money" are.

This, the first part deals with the Continental Op character blundering into a major crime while out investigating something entirely different and quite minor. He finds himself the captive of an unlikely gang consisting of an elderly couple, a frivolous young woman, a hard case thug, and a highly educated Chinese. Mostly through their own distrust of each other, he manages to disrupt their plans, leaving all but one of them dead or captured by the stories end, and only at that time, does he fully understand what he has found.

It's a witty, at times funny story, with Hammett's pithy observational powers at their best.