The Big Bang Theory 4x05 - The Desperation Emanation - Full Synopsis
Zack didn't end up being in the episode, he must have been cut when they had to write Penny out. And instead of being played by Edi Patterson like I saw last week, Joy was played by Charlotte Newhouse. Bernadette's still listed among the main cast.
The episode is called "The Desperation Emanation."
UPDATE: READ THE COMPLETE SYNOPSIS AT SOURCE! (All credits goes to Roxanne (ennaxor) from Fanforum!
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