Season 1

Wednesday evening is Halo evening. That's exactly what the four boys of the Big Bang Theory intend to do this Wednesday. When they are just about to begin, Penny bursts into Sheldon and Leonard's apartment. After a brief explanation it becomes clear that Penny has a house guest: Christie. She only intended to live with Penny until she had found a place of her own. But now Penny cannot get rid of her new "house mate." Penny has known Christie for a fairly long time, as they both come from Omaha. When she then mentions that Christie has had sex with every man from her hometown, Howard is suddenly missing. As Penny calms down a little, she discovers on her return to her apartment that Howard and Christie have already undertaken sexual activities and returns to the physicist's flat. Because one Halo player is missing, Penny offers to replace Howard, because she feels, as it were, guilty for the player's absence. Sheldon is skeptical, but he finds out in the course of the evening that Penny is a talented and dangerous player. When by the end of the evening there is no trace of Christie and Howard, Penny asks Leonard and Sheldon if she can spend the night at their place. In spite of Sheldon's doubts, the three agree and Penny gets to sleep on the sofa.

The next morning Howard appears in Penny's dressing gown, bursting with pride, to report on his previous night's adventures. A short time later, Christie picks him up to go shopping. As the "relationship" of the both grows a little bit, other problems come out. For example, Sheldon discovers in the China Restaurant that the usual meal will not work; since a person is missing, the entrees can not be divided evenly as was otherwise customary.

On the next halo evening, nearly a week later, Howard is still out and about with Christie and therefore has no time for Halo. When they want to invite Penny, they find she prefers to go dancing rather than playing Halo. Due to the disaster Sheldon bethinks if the equilibrium in their universe can be restored and what's more, none other than Howard Wolowitz. So the three are making their way to Howard to bring him to reason. As they got there, they witness a violent argument between Wolowitz and Howard's girlfriend Christe. He takes to his heels to save his skin and is very glad to see his friends. And thereby the Halo evening was saved.