Matthew McConaughey Reveals His 'Interstellar' Birthday Surprises

Kevin Frazier sat down with the Interstellar cast in Washington D.C. yesterday at the Smithsonian National Air & Space Museum for a Google+ Hangout, but prior to the sit-down, Kevin and Matthew McConaughey chatted about the actor's 45th birthday.

"I was able to be surprised by my wife three times during the day," says Matthew, who shares three children (Livingston, Levi and Vida) with wife Camila Alves. "First surprise: we got some quiet time that I didn't expect. Second surprise was her and the kids were off in the museum and I came in the door and "Surprise!" they had banners and all kinds of stuff. [Last] surprise: some friends were there and then we partied. So I got three good surprises."

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Interstellar is Christopher Nolan's first film since wrapping up The Dark Knight trilogy and stars Matthew and Anne Hathaway as astronauts who must find a new planet to replace a dying Earth. In addition to the high-stakes premise, the emotional aspect of the tale focuses on Matthew's character -- a father grappling with the conflict of having to leave his children behind for a larger cause: survival of the species.

Matthew told ET last month that his real-life children played a part in his decision to do the movie.

"The main impetus in my gut was I want to do this for my son, Levi," said Matthew. "He came to set and he saw all of our shuttles and the Endurance and everything, and he got to take some practical rides, and it was real for him. It was better than Disneyland."

Interstellar opens Nov. 7.