Private Investigator Philip Marlowe (Humphrey Bogart) is summoned to General Sternwood's office with an intriguing case to stop a man from blackmailing the general. The plot thickens when it is revealed that another investigator, who had been hired before, has previously disappeared.
Marlowe is introduced to the General's philandering daughers Vivian (Lauren Bacall) and Carmen (Martha Vickers) where he discovers that despite the General having very little influence in his own family, he is still insistent of keeping up the family honour.
As Marlowe searches for the illusive blackmailer, he begins to find that the case runs deeper than he originally anticipated, but, in order to respect the General's wishes he continues to follow the case regardless.
One of the details that stands out in The Big Sleep is the behaviour of the characters. In one scene Carmen attempts to flirt vivaciously with Marlowe but it quickly thrown out on her ear, with a swift "go away". It is refreshing to see this "politically incorrect" behaviour - and it is a big draw of older films.
In places, the storyline is difficult to follow; at the beginning the sisters appear to be the same character, and then Geiger, Brody and Mars become difficult to distinguish between. Once this has been overcome though, then you will be rewarded with an a thoroughly enthralling detective masterpiece.
Devilishly complicated, heavenly enthralling.