Ethan Hawke cheated on his wife Uma Thurman because he reportedly felt sure she was having an affair with movie maker Quentin Tarantino.

The REALITY BITES actor strayed with model JEN PERZOW, 22, while he was working in Canada, and, as he and Thurman attempt to save their marriage, friends claim he thought his wife had already been unfaithful - with her KILL BILL director.

A source tells American tabloid NATIONAL ENQUIRER, "Ethan was really ticked off because he always thought Quentin had a thing for his wife.

"Quentin and Uma are longtime pals and there's a real chemistry there since they made Pulp Fiction together.

"When people around the set (of Kill Bill) tattled to Ethan, he was really upset. Now Quentin feels he's going to get dragged into this nasty mess."

Meanwhile, Tarantino, who wrote Kill Bill as a birthday present to Thurman, is desperately trying to separate himself from the couple's marital problems.

In a new ROLLING STONE interview, the maverick movie maker insists Uma is nothing more than a muse, adding they have "a total partnership," and "there is nothing to that," when responding to questions about his involvement in the couple's problems.

10/10/2003 19:06