In the 1940s, Lorre moved to Hollywood, California (USA). Hollywood is a town where many movies are made. Lorre acted in many movies, playing foreign characters. Lorre played the role of Joel Cairo in the movie "The Maltese Falcon" (1941) and played the role of "Ugarte" in the movie "Casablanca" (1942). Lorre played the character of Dr. Einstein in the movie" Arsenic and Old Lace" (1944).