Little does he know the producer he loaned her to is still secretly schtupping her. Then there are two cases of costars cheating on their spouses with each other. Do actors do anything on set other than sleep together?

1. "There are all kinds of ways to get a job in Hollywood, but this one is particularly juicy. This married writer/producer/director wanted to direct this much anticipated movie. A movie for which there was a lot of competition. Well, one day the producer of the movie came over to the director's house to interview him for the job. While he was there the director's B- list movie and television actress wife showed up. She sat in on the interview and made it perfectly clear to the producer that she was perfectly willing to f**k him right there if it got her husband the job. The next day the producer came over and our actress and he had sex. The director got the job. What he might not have expected though is that his wife who has done this kind of thing before has continued to sleep with the producer." [CDaN]

2. "These two movie costars are cheating with each other. One is an A List male with a wife and the other B List maybe. They fell in love on the set of the movie and although filming is wrapped and the movie will be out soon, the two are coming up with a million ways to meet up. They are going in on some charity work together so they can be closer. The sad thing is, the A-lister's poor wife has no clue and brags to all her friends about her husband's fidelity. She is completely devoted to him, but he is telling his new actress girlfriend he'll be leaving his wife very soon. Not Liev Schreiber." [Liev Schreiber]

3. "Our actor is married to a women who seems like an odd choice for him. Our actress is engaged to a man who seems like an odd choice for her. However, since they've been working together, something has sparked between the two and they have taken to wearing each other out in private. The girl doesn't want this fling to spill over into real life when the gig is over. But she is open to the idea of the two of them working together on a future project." [Blind Gossip]