Death in Venice

The novel Death in Venice was written in German by Thomas Mann, and was first published in 1912 as Der Tod in Venedig.

A film version directed by Luchino Visconti was made in 1971, with Dirk Bogarde as Gustav von Aschenbach and Bjorn Andresen as Tadzio.

Warning: Wikipedia contains spoilers

Summary of the plot

Gustav von Aschenbach, knowing he has only a short time to live, travels to Venice, where he becomes obsessed with the androgynous beauty of the teenage boy Tadzio. A cholera epidemic has just broken out and von Aschenbach plans to leave but changes his mind because of Tadzio, even though he never even has the opportunity to talk to the boy. Eventually Gustav dies on the Lido beach. In the film, von Aschenbach is a composer; in the original book, he is a writer.