Bill Nighy and Domhnall Gleeson star in Richard Curtis' ('Love Actually') latest and, unfortunately, last directorial effort, 'About Time.' The two play a father-and-son duo with a unique family trait -- the men can all travel through time. While the film is a unique take on the rom-com genre, focusing primarily on Gleeson's Tim as he uses his gift to land a girlfriend (in Rachel McAdams), this familial relationship offers some of the film's most moving moments.

Part of how Curtis chose to depict and further their relationship was through the various ping pong matches, which the director told us comes directly from his relationship with his own father. As Nighy tells ScreenCrush, "[Gleeson's] really good at ping pong, and obviously I'm no good at all," having required several lessons to get a good volley going. "But he can't act."

As far as their offscreen relationship goes, "We had a brief affair, which was a very bad idea. It was not professional and we both regret it."

Aside from the principal and supporting cast,  'About Time' features some surprise cameos by two Richards -- Richard E. Grant and, perhaps most resounding, Richard Griffiths, who recently passed. "Seeing [Griffiths] work with Richard E. Grant, doing their scene together, was one of those treasured moments that you just say, 'I'm just lucky that I was there,'" said Gleeson. "I knew as it was happening that I was lucky to be there, and so I really tried to take it all in."

'About Time' is currently in theaters, and for more information on the film, watch our full interview with Bill Nighy and Domhnall Gleeson above.