Justin Timberlake put Ben Barnes off his step when he visited the set of period comedy EASY VIRTUE - because the British actor was dancing with the pop star's girlfriend.
Barnes admits he had enough trouble learning his moves for the scenes with Jessica Biel, who plays the actor's wife in the movie, without having Timberlake on set to watch him stumble.
He tells WENN, "It's not that he was on set all the time. I certainly didn't see him prowling around.
"He did come onto the set one day and it happened to be the day that we were dancing. I don't pride myself on my dancing, it's not my best talent.
"It was nerve-wracking to have him there, watching me with one eyebrow raised, dancing with his woman, very badly."