Jennifer Aniston's spoof video was "all" Justin Theroux's idea.

The actress starred in a hilarious commercial for SmartWater which is filmed as a mock home surveillance tape.

Jennifer makes light of all the rumours surrounding her private life in the video, which sources say was conceived by her fianc Justin.

"It was all Justin's idea. He wrote the ad and helped direct it too. They poked fun at all the constant rumours she hears about her being pregnant," the insider told British magazine Heat.

Jennifer proved that she can make light of the speculation surrounding her, including her famous 'Rachel' hairstyle, family planning and her fitness regime. However, the Hollywood beauty was not convinced about one subject that Justin broached.

"Justin wanted to go there with the Brangelina rumours and spoof all the stories about Jen, Brad and Ange - but Jen wouldn't let him," the source continued. "He thought it would be funny to take on the rumours once and for all and do a joke about her being secret friends with Brad and Ange, but she just couldn't do it.

"She can make fun of everything else but that."