The ‘Vow’ co-stars were shooting a scene where Rachel’s character – who has lost her memory – sees her husband, played by Channing, naked and the actor decided to play a practical joke on Rachel by having the props department make a huge prosthetic penis for him to wear.
Rachel told Stella magazine: “Channing got the props department to make a prosthetic member. Literally a fake penis. I didn’t know what to do. I thought, ‘Is this the real deal?’ It was very realistic. It was ridiculous, the scale of it.”
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Rachel, 33 – who lives in Toronto - is currently dating British actor and her ‘Midnight In Paris’ co-star Michael Sheen and admitted they have to make a huge effort to make their long-distance relationship work.
She explained: “Michael and I never spend more than three weeks apart – we rack up a lot of air miles – but you have to be quite adaptable in this business whether you are in a relationship or not. Trying to establish roots somewhere is a bit of a joke.”