WHAT IT'S ABOUT: Amy (Mayim Bialik) and Sheldon (Jim Parsons) are appearing on the kids' science series "The Professor Proton Show" _ Professor Proton now played by Wil Wheaton _ to discuss a theory they have discovered about symmetry (super-asymmetry, to be exact) when suddenly, the doorbell rings. Sheldon goes to open it and ... standing there, in the flesh, is William Shatner. Sheldon loses his cool, or what little he has of it anyway.
Meanwhile, it turns out Wheaton has struck up a friendship with Shatner because he's been hosting a secret celebrity Dungeons & Dragons tournament with some other celebrities, including the once-and-always Capt. James T. Kirk. The other celebs are Joe Manganiello, Kareem Abdul-Jabbar and Kevin Smith. Naturally, or inevitably, Leonard (Johnny Galecki), Howard (Simon Helberg) and Raj (Kunal Nayyar) are desperate to join the game, too.
MY SAY: The last time Shatner, 87, appeared in a live-action, prime-time sitcom as William Shatner was in 1996, in "The Fresh Prince of Bel-Air." The episode was titled "Eye, Tooth." Further details _ was it good, bad, dumb, indifferent? _ are inconsequential. The key point is that William Shatner has not appeared as William Shatner on a sitcom in 23 years.