German expressionism began in the early 20th century in Germany and focused on expressionistic set and lighting designs rather than narrative. Some key characteristics included contrasting light and dark, abstract patterns, and unnatural angles. The Cabinet of Dr. Caligari and Nosferatu are famous examples that use these techniques. After World War I, German expressionism influenced Hollywood and the development of film noir genres. Film noir heroes often have dark pasts and moral flaws that eventually bring them down, usually due to their involvement with femme fatales who blackmail or betray them. Humphrey Bogart's character in Casablanca and Officer Bud White in LA Confidential exemplify this type of flawed noir hero.