The guys enter a costume contest as members of the Justice League and convince Penny and Zack to join them.



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Episode cast overview:
Zack Johnson (as Brian Thomas Smith)


Penny starts dating Zack again. Used to being the target of bullying, Leonard, Sheldon, Howard and Raj instead bully Zack through their implications to him that he's stupid. Not fully realizing what they're doing until Penny points it out to them, the guys decide to apologize to Zack in the only way they can. Accepting their apology, Zack decides to start hanging out with them, much to Penny's chagrin. This hanging out leads to the idea that Zack should replace Leonard as Superman in their group Justice League of America costume for the New Year's Eve party at the comic book store, with Penny the sixth wheel as Wonder Woman. These actions lead to questions from Leonard to Penny about why she's back together with Zack. Written by Huggo

Plot Summary | Plot Synopsis


Comedy | Romance


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Release Date:

16 December 2010 (USA)  »

Company Credits

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Technical Specs


Sound Mix:


Aspect Ratio:

16:9 HD
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Did You Know?


In Sheldon's incredibly short trip to the Grand Canyon at the end, the music accompanying him is the interlude "Flight of the Bumblebee" from the opera "The Tale of Tsar Saltan" by Nikolai Rimsky-Korsakov. See more »


Sheldon incorrectly states that although Amazon's tend to be very beefy gals they are not blonde. In reality there are several blonde Amazons. As an avid comic book reader Sheldon should know this. See more »


[first lines]
Raj Koothrappali: [playing a card] Water Demon.
Howard Wolowitz: [playing a card] Ice Dragon.
Leonard Hofstadter: [playing a card] Lesser Warlord of Ka'a.
Sheldon Cooper: Not so fast.
[playing a card]
Sheldon Cooper: Infinite Sheldon.
Leonard Hofstadter: Infinite Sheldon?
Sheldon Cooper: Yes. Infinite Sheldon, it beats all other cards - and does not violate the rule against homemade cards because I made it at work.
Leonard Hofstadter: You understand why people don't want to play with you?
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References Doctor Who (1963) See more »


The Big Bang Theory Theme (Instrumental)
Composed and Performed by Barenaked Ladies
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User Reviews

The cast has a New Year's Eve costume party on "The Justice League Recombination" ep of "The Big Bang Theory"
8 October 2011 | by (Baton Rouge, La.) – See all my reviews

In this last season ep of "The Big Bang Theory": Penny's ex Zack (Brian Smith) is with her again and she's not too happy at the way the boys are making fun of him. Turns out Zack himself has figured it out too and also doesn't like it. So Leonard apologizes while the rest come with him to see him beat up. That doesn't happen since Zack forgives when Milk Duds (a Sheldon suggestion) are offered. Later at the comic shop, where Zack is excited about the Archie section, he gets an invite for the place's New Year's Eve costume party to be Superman to Leonard's consternation since he was the Man of Steel previously. At least he doesn't have to be Aquaman who the actual wearer Raj thinks sucks. Penny is picked to be Wonder Woman in order to complete the Justice League group but wavers with both Zack and ex Leonard coming...Another hilarious ep with some touching moments between Penny and Leonard. Especially loved the end. So on that note, "The Justice League Recombination" is another very worthy ep of "The Big Bang Theory".

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