They say you're not supposed to meet your heroes, so what will happen when The Big Bang Theory's Sheldon comes face to face with none other than Leonard Nimoy? Well, according to TVLine, he'll be just fine, as it will all be in his head. The Star Trek actor will appear as Spock, or more specifically Spock's voice, in the March 29 episode of the CBS sitcom.

"For years, we thought it would be fantastic to have Leonard Nimoy appear on the show and we think we’ve found a really different and fun way to make that happen," Executive Producer Steve Molaro told The Hollywood Reporter. "As thrilled as we are he's doing it, we're even more thrilled just to get our pictures taken with him.”

Fans of the sitcom will note that Sheldon showed real emotion when Penny gave him a napkin used and signed by Nimoy in the second season and also got upset recently when he received a Zachary Quinto Spock standee instead of a Nimoy one. This will not be the first cameo by an original Star Trek cast member, either: George Takei also had a guest spot, popping into Howard's sleeping mind along with Battlestar Galactica's Katee Sackhoff to help him out with the ladies.