Bazinga, nerds! 2013 has finally arrived, and with it comes the return of 'The Big Bang Theory' in this Thursday's "The Egg Salad Equivalency." Previously we've seen some looming threats to Leonard and Penny's renewed relationship, but could the biggest bang yet be on the horizon? Could we have perhaps phrased that more carefully? Check out the latest clips from 'The Big Bang Theory's January return inside!

While it seems that just about all of the 'Big Bang Theory' players (save Raj) have found themselves healthy, stable relationships, Leonard may soon find himself in more trouble than he realizes. Not only does Sheldon's assistant Alex (Margo Harshman) have eyes for Leonard in a way that could complicate things with Penny, but Sheldon's interference might get them all in the hot-seat!

This Thursday's 'The Big Bang Theory' return "The Egg Salad Equivalency" will also see 'Southland' star Regina King appearing as university director of employee relations Mrs. Davis, investigating Sheldon for claims of sexual harassment, but why wait until then? CBS has released two fresh clips of the upcoming episode, in which Leonard's complacency with the situation soon gives way to a much larger problem.

Check out the newest clips from 'The Big Bang Theory' below, and tell us what you want to see from the second half of the season in the comments! Don't forget to watch "The Egg Salad Equivalency" Thursday on CBS!

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