Up to THE LOST WEEKEND, Billy Wilder was a talented script writer from Austria, who had done (after some noise and badgering) several movies that he and Charles Brackett wrote the scripts for, but the way he felt they were intended. So Paramount let him go ahead and produce and direct their own films, and he proved the studio was wise to do so.
By 1945 Wilder had done a wacky comedy, THE MAJOR AND THE MINOR about a military academy. The film was a box office success. It was followed by FIVE GRAVES TO CAIRO, which gave a fictional account of the war in North Africa, and gave a stunningly good performance by Eric Von Stroheim as General Erwin Rommel. But Wilder and Brackett wanted to tackle a "message" picture. They found one in the best selling novel THE LOST WEEKEND by Charles Jackson. It tackled the issue of alcoholism.
Alcoholism had actually been noted in motion pictures almost from the start, usually in comedies where a character (possibly the star, like Chaplin in ONE A.M.) would do his or her business while tanked. The 19th Century drama, THE DRUNKARD, was used by W.C. Fields in THE OLD FASHIONED WAY as the play Fields' troop is putting on. Another version of THE DRUNKARD was made into a full movie in 1940 called THE VILLAIN STILL PURSUES HER, with Alan Mowbray and Buster Keaton.
Now and then a more serious problem would be shown. D.W.Griffith made his last film in 1931 about alcoholism, THE STRUGGLE (which was a flop). In SADIE MCGEE, Joan Crawford marries Edward Arnold who is an alcoholic (she eventually helps on this problem). Aside from Griffith's flop nobody made a serious film about the disease. Wilder and Brackett turned in a good screenplay that did just that.
Don Birnan is a young man who claims to be a writer, but has published very little. Three people are aware of his weakness: Don's older brother Wic, the local bartender Nat, and Don's girlfriend Helen.
The crisis occurs the last weekend of the summer. Don is to go with Wic and work on his novel. But he disappears when he is supposed to be ready to leave. Wic has rearranged his own life for Don and is fed up. He leaves to go to the country house alone. He tells Helen not to waste her own life with Don, as Don is so far gone that he is not worth it. Helen (more troubled than Wic) does make herself scarce too. So Don, when he gets home, finds that he is really all alone on that long weekend.
Well not totally alone - he's inventive, our Don. He hides bottles of liquor all over the house (the old joke about the whiskey bottle hidden in a chandelier comes from this film). Wic does try to find the hiding places, but Don comes up with new ones (including suspending a bottle from a window by a string. However even this is of little use, as Don's demons drive him deeper and deeper into drinking. He has little money left, and soon is out of credit at Nat's (who hates to give him credit for drink because it's harmful to Don). He even steals a purse at one point. He tries to hock his typewriter. All for the money for a drink. And then he ends up in Bellevue's "Drunk Tank" where he meets the cynical nurse Bim, who has heard all the remorseful stories of reform from Don and his ilk forever.
There is far more to the screenplay than this synopsis suggests. Don's behavior is centered only on getting the sauce into him - and he does not care who is "inconvenienced" along the way, so that he finds himself quite isolated by the conclusion of the film. The movie's ending is hopeful, but just vaguely that. Somehow Don is such a weak character we can not be sure if he will ever turn his life around again.
Wilder used Ray Milland in this film, and it is usually pointed out that Milland was normally in comedies like EASY LIVING, SKYLARK, or Wilder's own THE MAJOR AND THE MINOR. But he had played serious parts, most notably in BEAU GESTE, I WANTED WINGS, and (more recently) THE MINISTRY OF FEAR and THE UNINVITED. But Don Birnan was the first three dimensional figure he tackled, and he did splendidly in it. His Oscar guaranteed a decade of stardom, and a really interesting career afterward in directing and character parts. Jane Wyman plays Helen as a character who struggles to recall the man she loves up to the conclusion of the film - his weakness constantly threatening the relationship. Philip Terry's Wic is equally good, putting on the best face possible, until the straw breaks the camel's back. As Bim, Frank Faylen is understandably fed up with his ward charges at Bellevue - all claiming they aren't ill, but quite evidently recurring so. And Howard Da Silva, normally playing villains in the 1940s, played the understanding Nat as harsh but compassionate - he wants Don to straighten up and write as he claims he can.
How real is the story here? There is an anecdote that Milland mentions in WILD EYED IN BABYLON, where he and Da Silva were in the set of the bar rehearsing a scene. They were interrupted by a bowler hatted little man with a familiar face, who came in and ordered a shot of whiskey. He paid for it, gulped it down before the two actors, and left the bar. They watched him go and did not say a word. It was Robert Benchley, working on another picture at Paramount at the next set. And Benchley had his own alcohol problems too.