Hammett is drunk and sick, and he's being threatened by a killer. He needs help, and who better than to strap on a gun and come to his aid than Ray Chandler? Well, okay, maybe Chandler's not your idea of a tough guy, but this is fiction. Anything goes.
The blurb on the back cover is from Peter McCurtin, who says, "A wild idea but it works. The writing is smooth, the action violent." The last statement is true. Everything else is a lie, including the words "a" and "the." (You know who I stole that from, right?) The writing is awful, and the idea doesn't work at all. If you want to find out why Hammett was such a success, read Chandler, where everything goes wrong. Instead being published by a big-name hardover house, Chandler came from Belmont-Tower, one of the really low-end paperback publishers.
Of course I could be wrong about this. Chandler could be an undiscovered classic. You'll have to read it and decide for yourself.