No writers were credited on this draft I read - the screen credits attribute it to Raymond Chandler as were as Czenzi Cermonde and Whitfield Cook, although apparently nothing of Chandler's work remains. (Having said that you really need to double check those claims).
It's a very well structured, highly entertaining piece. The concept maybe is a bit silly but it's at least different: weird Bruno suggests to Guy that they murder each other's enemies - Guy has a slutty wife and Bruno has a mean dad. Bruno is the only one who is serious about it.
The beginning is almost like a play with a long chat between Bruno and Guy. Then things get more cinematic with the murder of Guy's wife, full of great visual ticks and devices. It's a bit wonky that Guy doesn't tell the cops straight away about Bruno.
Bruno is a fantastic role - smart, pathetic, whiny, cunning, lonely, mother fixated. Guy suffers in comparison - a bit of a self-righteous dill, too silly to not tell the police straight away about Bruno and to try and win a tennis game quickly instead of throwing it. Anne is dull as is her father. I wish more use had been made of Bruno's mother, she was fun. So is Anne's gossipy sister and Guy's trampy wife.
Hitchcock complained about the dialogue but I thought it was fine. None of it felt too "Chandler". Solid story though.