Peter Lorre (26 June 1904 – 23 March 1964) was an Austrian-born Americanactor of Jewish descent.

Lorre caused an international sensation with his portrayal of a serial killer who preys on little girls in the German film M (1931). In enforced exile in Hollywood, he later became a featured player in many Hollywood crime and mystery films. The Maltese Falcon (1941), his first film with Humphrey Bogart and Sydney Greenstreet, was followed by Casablanca (1942). Lorre and Greenstreet appeared in a further seven films together.

Frequently typecast as a sinister foreigner, his later career was erratic. Lorre was the first actor to play a James Bond villain as Le Chiffre in a TV version of Casino Royale (1954). Some of his last roles were in several horror films directed by Roger Corman.

Lorre soon settled in Hollywood, where he specialized in playing sinister foreigners, beginning with Mad Love (1935), directed by Karl Freund. He starred in a series of Mr. Moto movies, a parallel to the better known Charlie Chan series, in which he played John P. Marquand's character, a Japanese detective and spy. Initially positive about the films, he soon grew frustrated with them, "the role is childish" he once asserted, and eventually tended to angrily dismiss the films entirely. He twisted his shoulder during a stunt in Mr. Moto Takes a Vacation (1939), the penultimate entry of the series. In 1939 he attended a lunch at the request of some visiting Japanese officials; Lorre wore a badge which said "Boycott Japanese goods".

Late in 1938, Universal wanted to borrow Lorre from Fox for the role ultimately performed by Basil Rathbone in Son of Frankenstein (1939). Lorre declined the role because he thought his menacing roles were now behind him, although he was ill at this time. He had tested successfully in 1937 for the role of Quasimodo in an aborted MGM version of The Hunchback of Notre Dame in 1937, according to a Fox publicist one of two roles Lorre much wanted to play (the other was Napoleon). By now, frustrated by broken promises from Fox, Lorre had managed to end his contract, and went freelance for the next four years. In 1940, Lorre appeared as the anonymous lead in the B-picture Stranger on the Third Floor, reputedly the first ever film noir. The same year he co-starred with horror actors Bela Lugosi and Boris Karloff in the Kay Kyser movie You'll Find Out.

The War years (1941–1945)
Lorre played the role of Joel Cairo in The Maltese Falcon (1941) and portrayed the character Ugarte in Casablanca (1942). While Ugarte is a small part, it is he who provides Rick with the 'Letters of Transit', a key plot device. Lorre made nine movies altogether with Sydney Greenstreet counting The Maltese Falcon and Casablanca, most of them variations on the latter film, including Background to Danger (1943, with George Raft); Passage to Marseille (1944, reuniting them with Casablanca stars Humphrey Bogart and Claude Rains); The Mask of Dimitrios (1944, with character actor Greenstreet receiving top billing); The Conspirators (1944, with HedyLamarr and Paul Henreid); Hollywood Canteen (1944); Three Strangers (1946), a suspense film about three people who are joint partners on a winning lottery ticket starring top-billed Greenstreet, Geraldine Fitzgerald, and third-billed Lorre cast against type by director Jean Negulesco as the romantic lead; and Greenstreet and Lorre's final film together, suspense thriller The Verdict (1946), director Don Siegel's first movie, with Greenstreet and Lorre finally billed first and second, respectively.

Lorre also branched out into comedy with the role of Dr. Einstein in Frank Capra's version of Arsenic and Old Lace (released in 1944), and starring Cary Grant and Raymond Massey. In 1941, Peter Lorre became a naturalized citizen of the United States.

Writing in 1944, film critic Manny Farber described what he called Lorre's "double-take job," a characteristic dramatic flourish "where the actor's face changes rapidly from laughter, love or a security that he doesn't really feel to a face more sincerely menacing, fearful or deadpan."