Celeb snitches tell us that the director of the film “Grindhouse,” Robert Rodriguez (the guy behind the atrocity known as “The Adventures of Sharkboy and Lava Girl) engaged in a tawdry on-set affair which lead to Rob’s wife kicking him to the curb and a one month hiatus on filming.

“It was the worst-kept secret on the set. They were going off to his trailer, having meals together,” says a dishing source. “Rose thought some of the crew were treating her differently, and the attitude was, like, well what do you expect when you’re fucking the director?”

“When Elizabeth (the wife) found out, there was an eruption of emotions - an emotional volcano,” the spywitness continued.

A Dimension Films spokeswoman would only comment: “The hiatus had nothing to do with Robert’s personal life.”