It’s a night of a thousand guest stars as The Big Bang Theory continues moving through its home stretch. “The D & D Vortex” opens with a couple of Star Trek pals and broadens its celebrity scope from there…

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Wil Wheaton invites Nobel Prize contenders Amy (Mayim Bialik) and Sheldon (Jim Parsons) onto his “Professor Proton” show to try to explain to the nine-year-olds in his audience what their Super Asymmetry discovery is all about. As Sheldon is failing to keep it simple, a surprise visitor arrives: William Shatner!

The video of Sheldon nervous-vomiting on his hero goes viral, and in addition to embarrassing him it leaves Sheldon burdened with a need to apologize to Shatner. 

Sheldon goes to Wil’s house to ask for access to Shatner for said apology, and Wil refuses. Before Sheldon leaves Wil’s door, though, he hears Shatner and others calling Wil back to what is certainly a secret celebrity game of Dungeons & Dragons. Wil shoos him away, and Sheldon reluctantly leaves. 

After being soaked by Wil’s sprinklers while trying to peek in the window, Sheldon rushes to tell the gang what he’s stumbled upon. They’re all eating dinner together at Penny (Kaley Cuoco) and Leonard’s (Johnny Galecki), and the guys flip their lids when Sheldon tells them. The evening devolves into them using graph theory to deduce who else might be part of the game. 

As the girls bemoan the reality of the rest of their lives with these husbands, the guys settle on a likely participant and look at his Instagram to see if he’s posted anything about playing D&D. Sure enough, they find a photo of the game in progress at Wil’s, featuring Shatner, Kevin Smith and others.

In the background of the photo, there’s something ghostly white behind one of the players. It’s Stuart (Kevin Sussman).

That night, Howard (Simon Helberg), Raj (Kunal Nayyar), Leonard and Sheldon lie in wait at the Wolowitzes’ house. When Stuart gets home, he walks into the kitchen and is surrounded. They force him to acknowledge that he’s part of Wil’s weekly game, and that they’re playing with wereboars having 12d8 + 24 hit dice. The pressure of being caught is too great for Stuart, and he calls Wil to withdraw from the game. 

Raj and Howard call Wil, with Howard impersonating Shatner (and Christopher Walken) to try to get information about the game. They fail, but Leonard gets a shock when Wil calls him and invites him to take Stuart’s seat on the condition that he not tell the other guys. Leonard agrees without hesitation. 

At the game, a starstruck Leonard finds himself seated with Wil, Shatner, Kevin Smith, Kareem Abdul-Jabbar and Joe Manganiello. When he gets home, he’s on cloud nine and needs to tell someone… so he tells Penny, counting on her disinterest in D&D to make it safe. He doesn’t know Kareem, though, so he’s surprised by Penny’s excitement about him. And he completely underestimates the appeal of Joe Manganiello, which is his downfall. 

Penny is unable to keep the secret that Wil’s game includes one of the stars of the Magic Mike films, so the next day she tracks down Bernadette (Melissa Rauch) and Amy at Bernie’s house and blabs to them. They head straight to the Professor Proton set to suck up to Wil, suddenly remembering their limited experience with D&D as being super fun. 

Minutes later, Wil bursts Leonard’s bubble by disinviting him from future games because he couldn’t keep his trap shut. In response, Leonard decides he doesn’t need to keep the secret from the guys anymore. At first they’re hurt that he agreed to keep a secret from them, but then they realize there’s a seat open in the game again and they rush to Wil’s to beg him to let one of them play. Wil refuses, shaming them for trying to take advantage of his celebrity connections. 

Fast forward to the guys getting ready to play their own D&D game and deciding they should invite Wil to show him that they like him for him, and not for who he knows. They call him, but he says he’s not available. He’s at his house, where his game is in full swing, and the girls have joined. Bernie and Amy are both creeping Joe Manganiello out a little, and Penny is impressing Shatner with her moxie. (And he’s impressing her with his “grandpa words.”)

Wil decides the guys deserve to see what’s going on and sends them all a selfie of the group with the girls. Their phones buzz simultaneously, and they unanimously agree that they do deserve it. 

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