The Water Engine is an American historical drama television film directed by Steven Schachter and written by David Mamet, based on his 1977 play of the same name. The film stars Patti LuPone, William H. Macy, John Mahoney, Joe Mantegna, and Treat Williams. It was released on TNT on August 24, 1992.

Plot

Charles Lang works at a menial job at a factory and lives with his blind sister Rita in an apartment in Chicago during the 1934 World's Fair. But he is also an amateur inventor, and the play centers around a machine he designs that can create electricity from distilled water. Seeking to patent his idea, he finds a lawyer, Mason Gross, in the phone book and shows him the machine, but Gross’s motivations seem to differ from Lang’s. Gross recruits another lawyer, Lawrence Oberman, and together they menace Lang and eventually his sister. It is heavily implied that the two of them serve the corporate establishment whose profits Lang’s engine threatens.