Sometimes a love scene is more than just love scene.
While most actors filming a love scene are acting, occasionally an on-screen romance will spillover into real life. Take the latest example, "Mad Men" star Vincent Kartheiser and his on-screen love interest this season, played by Alexis Bledel.
Bledel played Beth Dawes, a housewife who has an affair with Kartheiser's character, Pete Campbell.
Though their romance came to a suprising end on the recent season finale, the bigger surprise appears to be that they may be dating in real life.
A fellow passenger on a flight with the pair last weekend reported to Crushable.com that they exhibited some public displays of affection while seated in two middle seats, one behind the other.
"He was leaning over the back of his seat talking to her and leaned over and kissed her," the source said.
Bledel, the former star of "Gilmore Girls." admitted in a recent Q&A with AMC, which airs "Mad Men," that she was nervous about filming her love scenes with Kartheiser.
"(Vincent) noticed, and made it much better for me by just sort of making sure I felt comfortable," she said. "He kind of helped me take the edge off a little bit just by being nice.
Click through to see six other kissing co-stars who became partners in real life:
|Kelly Ripa and Mark Consuelos|
Before Kelly Ripa paired up with Regis, she was paired with her future husband Mark Consuelos on the ABC daytime drama, "All My Children." Consuelos played Ripa's onscreen lover Mateo Santos. But apparently sparks continued to fly offscreen as well. After a year of dating, Ripa and Consuelos eloped in Las Vegas in May 1996. In June 1997, they welcomed their first child Michael Joseph, followed by Lola Grace in 2001 and Joaquin Antonio in 2003.
|Kristen Stewart and Robert Pattinson|
After months of are they or aren't they dating, Kristen Stewart let slip in October 2011 that she was indeed dating her "Twilight" on-screen love interest Robert Pattinson. The couple remain fiercely private about their love life, even as they appear together publicly and even share a kiss or two, but more than once KStew has referred to Pattinson as her boyfriend.
|Brad Pitt and Angelina Jolie|
By now, everyone knows Hollywood's most famous couple, Brad Pitt and Angelina Jolie, met in 2003 on the set of "Mr. and Mrs. Smith," in which they played married assassins. Pitt was married to Jennifer Aniston at the time, and though Jolie has maintained she remained just friends with Pitt until his marriage broke up in 2005, sparks were clearly flying on the set. "I think a few months in I realized, 'God, I can't wait to get to work,' " she told Vogue in 2006. Parents to six children, the pair are now engaged.
|Will Smith and Jada Pinkett Smith|
Before she became Will Smith's real-life partner, Jada Pinkett Smith auditioned to be his girlfriend on "The Fresh Prince of Bel-Air" in 1990. She didn't get the gig -- she was considered too short, so the role went to actress Nia Long -- but she did get the man, and the wedding ring in the end. Will and Jada stayed friends and began dating in 1995. They married in 1997, and have two children, Jaden and Willow, who are following in their famous parents' footsteps.
|Anna Paquin and Stephen Moyer|
Anna Paquin and Stephen Moyer began dating soon after their HBO show "True Blood" debuted in 2008 and they shared their first on-screen kiss. They kept their relationship under wraps, though, finally announcing their engagement in August 2009. Married a year later, they are now expecting their first child in the fall.
|Jennifer Garner and Ben Affleck|
You'd think Ben Affleck would have shied away from dating his co-stars after his "Gigli" disaster with then fiance Jennifer Lopez. Instead, Affleck began dating another Jennifer -- Jennifer Garner -- after they played comic-book superhero lovers in 2003's "Daredevil." The pair made their first public appearance as a couple attending the Boston Red Sox's opening World Series game in October 2004. They married in 2005, when she was pregnant with their first child. She recently had their third child.