Natalie Portman's passionate kiss with Chris Hemsworth in the new Thor movie has been exposed as a fake as the actor was actually embracing his real life wife in the scene.

The Oscar winner plays the Aussie hunk's love interest Dr. Jane Foster in this year's (13) superhero sequel Thor: The Dark World, but she was unable to attend a number of re-shoots as she was busy working on a new project.

Rather than hire another actress to stand in for Portman for a kissing scene, producers asked Hemsworth's wife Elsa Pataky to take her place.

Portman says, "It was for re-shoots (after the film was finished) and he was working in Hong Kong and I couldn't get there because I was working on my own film. So they put his wife in my wig and costume, that's why it is so passionate. It was such a perfect solution, wasn't it."