Continuity mistake: After driving Lauren Bacall home from Eddie Mars' place Marlowe walks into his apartment and we see the number 206 on the door. In the next shot from inside we see another door that doesn't have 206 on it. (01:17:05)
The Big Sleep (1946)
Ending / spoiler
Directed by: Howard Hawks
Starring: Humphrey Bogart, Lauren Bacall, John Ridgely, Martha Vickers
Marlowe (Bogart) deduces that Carmen murdered Regan, and that Vivian was uncooperative with him because she was trying to protect her sister by covering it up. The coverup caused six people to be killed. Marlowe and Vivian reach a compromise; Eddie Mars (accidentally killed by his own gang) will be blamed for the murder. They will also tell this to Carmen and Vivian's father to protect him from the shame. And Carmen will be sent to a mental institution instead of being turned in and facing justice.
JJ Lison
More mistakes in The Big Sleep
Vivian: You go too far, Marlowe.
Marlowe: Those are harsh words to throw at a man, especially when he's walking out of your bedroom.
Trivia: At the end of the movie Lauren Bacall says to Marlowe "Phil, there's two men out back behind some trees". This is the only time in the movie that she refers to him by his first name. (01:49:45)