Cameron Diaz and Justin Timberlake may have just been acting, but the couple gets down and dirty in Bad Teacher. In the film, Diaz plays a recently dumped, gold-digging grade school teacher who takes a liking to the sexy new substitute (Timberlake). Even though they had their clothes on, the movie’s sex scene was inevitably a bit uncomfortable. “Yes, yes. It was just [an] absurdity, a form of hilarity for all of us involved,” Diaz told People magazine of getting in bed with her ex of three years. But Bad Teacher director Jake Kasdan said the whole set enjoyed the experience. “They got in there and started doing it,” Kasdan told People magazine. “And it was so funny, we just couldn't stop shooting it. And we were doing it almost the whole day. And really crying, laughing at the [video] monitors.” Gemma LaMana / Sony Pictures Entertainment Inc. After a high-profile romance in 1998 with her Shakespeare in Love costar Ben Affleck, Gwyneth Paltrow had her eye on her ex to star alongside her in the 2000 film Bounce. The movie follows a smooth-talking advertising executive, Buddy, who gives up his plane ticket to a man trying to get home to his family for Christmas. But after the plane crashes, Buddy tracks down the wife (Paltrow) and, of course, the two fall in love. The hubbub surrounding Affleck and Paltrow off-screen, however, was equally scandalous. Affleck told Entertainment Weekly that he was surprised when Paltrow called him in 1999 to ask him to work with him on Bounce. “We had broken up and it was in that phase where it’s obviously difficult,” the actor told EW. He added: “I'm not somebody who's known for having great relationships with their ex-girlfriend. I've never understood those guys. How the f--- does that work? I mean, who is friends with all of their exes? Appropriately, all my exes hate me. But I realize that that was largely a mark of my own failings in the past because, though it hasn't been easy, I have been able to continue a relationship with Gwyneth that's really valuable to me.” The two pulled it together to make the movie happen, but Bounce barely made back its $35 million budget. Eric Lee / Miramax Films / Newsmakers Shortly after Julie Christie became internationally known for her roles in Darling and Doctor Zhivago, the British starlet earned an Oscar nomination for Robert Alterman’s 1971 film McCabe & Mrs. Miller, which co-starred her then-boyfriend Warren Beatty. The couple, who met at a reception for Queen Elizabeth II, was one of the most-celebrated of the late ‘60s and early ‘70s. In the end, however, they wanted different things. Christie and baby-obsessed Beatty split in 1974, but that wasn’t the end of them on screen. A year later, their movie Shampoo—complete with steamy scenes—hit theaters and in 1978, they reunited for the blockbuster comedy Heaven Can Wait. In the film, Beatty plays a backup NFL quarterback who dies, argues his way back to Earth in another man’s body and falls for Betty Logan (Christie). Though the experience reportedly prompted Christie to leave Hollywood for a while, she looks back fondly on her relationship with Beatty. “When I see someone like Warren, with his four kids, there is that wonderful recognition of the life we have led,” Christie told The Guardian in 2007. “And a terrific sense of mortality, which is like a blessing almost: you suddenly realize what life is about.” AP Photo Much like their characters in the 2010 romantic comedy Going the Distance, Drew Barrymore and Justin Long could not seem to make up their minds about whether or not to date. They started seeing each other in 2007, split in 2008, reunited in 2009 and broke up for good in 2010. Despite their on-again-off-again cycle, Long and Barrymore’s chemistry on-screen was apparent in Going the Distance. “I loved getting to do a film with someone that I do have a history with and we could bring a tremendous amount of honesty to it,” Barrymore told The Daily Mail. “We sort of saw that as a surreal opportunity and maybe it will feel a little more relatable-to because it is kind of real.” Long added: “The truth is, we do love each other. I pray to God she's always in my life. We were friends before this, and at the heart of what we are and will be friends.” In a perfect example of typecasting, real life exes Elizabeth Taylor and Richard Burton famously reunited in 1983 for Private Lives, a comedy about an ex-husband and wife who abandon their new spouses after a chance encounter on their honeymoons and try to make it work. Burton and Taylor had been married twice before: first in 1964 and later in 1975, only 16 months after their first divorce. The couple divorced for the second time a year later. As Burton told New York magazine, the Private Lives casting was no accident. “It’s all purposeful, what we’re doing,” Burton said. “We’ve even discussed the strategy of what to say when the inevitable dull question crop up about our reunion becoming a reconciliation. The set piece is all organized. Elizabeth pretends she hasn’t heard, and I say ‘Next question.’” AP Photo After three children and 13 years together as Hollywood’s beloved husband and wife, Demi Moore and Bruce Willis ended their marriage in 2000. But the unconventional former couple has managed to maintain a friendship—even going on vacation with their daughters to Disney World and dining together as an extended family. Moore and Willis, who starred in Mortal Thoughts together in 1991 and both lent their voices to 1996’s Beavis and Butt-Head Do America while they were married, returned to the screen for the 2003 film, Charlie’s Angels: Full Throttle. The movie marked Moore’s career comeback. With her notably toned physique, she played a former angel and the story’s villain, while Willis made a small cameo in the film. They showed up at the Charlie’s Angels premiere with their daughters and Moore’s now husband Ashton Kutcher in tow. Clark Jones / AP Photo In 2005, John Krasinksi, TV’s most beloved coworker on The Office, dated actress Rashida Jones. But the public was more interested in the relationship between Krasinksi’s character Jim and Dunder Mifflin’s secretary, Pam (Jenna Fischer). Audiences were then introduced to Jones in 2006 when she joined The Office as Karen, who came between the star-crossed co-workers. Jones insisted that it wasn’t awkward with Krasinksi on set. “He was incredibly supportive of me getting this job, and for the most part, if you go out with somebody and it doesn’t work out, there’s always a reason why you liked the person to begin with,” Jones told Us Weekly. Though her four-season stint on the series has since ended, Krasinksi—who is now married to actress Emily Blunt—still has a warm place in his heart for Jones. “I think it’s pretty obvious why Rashida is where she is. I walk into a room and I’m always the 34th person to say hi to her. Everyone falls in love with her,” Krasinksi told Entertainment Weekly. Justin Lubin / NBCU Photo Bank / AP Images Although Jack Nicholson claims Anjelica Huston beat him up after he admitted to impregnating another woman, five years was enough time to smooth things over. In 1995, the actors, who dated on-and-off for 17 years, starred together in Sean Penn’s The Crossing Guard as a divorced couple who lost their daughter to a hit-and-run incident. Famed critic Roger Ebert noted that “the fact that Huston is Nicholson's own ex-partner adds poignancy to a late-night scene where they talk about the good times they had together.” Huston said that she was “not really scared” to work with her former longtime boyfriend. “I liked the script and I like Sean and I had a good meeting with him. I think initially Sean was more scared to ask me whether I'd be interested,” Huston told Tribune News Service. “So that was comforting. I think Jack is a phenomenal actor. I’ve known Jack a long time. We have sort of a shorthand when we work together.” Liaison / Getty Images The two Brits met in 1991 during a production of Chekhov’s The Seagull and began a nearly decade-long relationship, which produced their daughter Lily. Beckinsale and Sheen split in 2002 shortly after starring in Underworld, a thriller about the history of vampires and werewolves. Beckinsale began dating the film’s director Len Wiseman, suspiciously close to her breakup with Sheen. Still, she insists he wasn’t the reason she left Sheen. “It was always rather odd to me when I'd get that 'Oh, what a slut' remark. Oh, she ditched the father of her child and ran off with somebody else,’” Beckinsale told Allure in 2006. “I mean, look around this town and tell me one other person who's slept with only two people in a decade. I might just be the only one.” Wiseman and Beckinsale married in 2005 and the newlyweds and Sheen united again for Underworld: Evolution in 2006 and Underworld: Rise of the Lycans in 2009. “It was obviously not easy, but in the end it was absolutely fine,” the brave Sheen said of filming the Underworld sequels. “He’s a lovely bloke, Len, and I never felt like anything had gone on behind my back.” Sheen will not be part of the franchise’s fourth installment in 2012, Underworld: New Dawn. Kevork Djansezian / AP After a five-year marriage spent on separate coasts—she was in New York while he played basketball for the Los Angeles Lakers—and tabloid infidelity rumors, Vanessa Williams and Rick Fox divorced in 2004. But the pair played it cool in 2007 when Fox guest starred on ABC’s Ugly Betty, in which Williams played the cutthroat magazine editor Wilhelmina Slater. The basketball veteran played her bodyguard for two episodes. “Things get heated [between their characters],” a source told People magazine of the cameo, which did involve a kiss. “We had a ball,” Williams told Access Hollywood of working with her ex. Fox added: “We see each other a lot with our daughter that we share custody of and raise together. Things have gone well in divorce so we finally got it right. But it is, it is exciting to be working finally together.” KAREN NEAL Karen Neal / ABC / Getty Images Little did Diane Keaton know that her famous relationship with filmmaker Woody Allen would be the romance that would make her career. The two began dating in the early ‘70s and went on to make eight films together between 1972 and 1993. While Keaton and Allen officially ended their relationship in 1979, they found themselves together again for Allen’s 1993 film Manhattan Murder Mystery. The movie follows a couple that enters an amateur criminal investigation after their neighbor’s odd reaction to his wife's sudden death. Hollywood had missed the goofy duo, as Keaton’s friend and fellow actress Carol Kane told The New York Times: “They are a classic comedy team, like Laurel and Hardy, Gracie and George. They are brilliant apart, but they get huge together." And seemingly, she was right—Keaton earned a Golden Globe nomination for her performance. Allen hopes to work with his repeat on-screen companion again. “I'd love to have a wonderful tour de force part with Diane Keaton but the problem is… doing what?” he asked The Guardian in May. “They don't want me flirting with Diane Keaton… Nobody wants to see two septuagenarians get it on.” He still credits Keaton with helping him write female characters. “They were cardboard figures before her, and I made no effort to change it,” Allen told The Guardian. “But after I met Keaton I could write women, and only write women, that was all that interested me.” Gamma-Keystone / Getty Images