03/30/2012 04:03 am ET Updated Mar 30, 2012

'The Big Bang Theory': Leonard Nimoy Voices Tiny Spock Action Figure As Sheldon's Conscience (VIDEO)

"The Big Bang Theory" (Thu., 8 p.m. ET on CBS) has never had any problem scoring major genre guest stars, but they certainly hit the jackpot this week, by nabbing one of Sheldon Cooper's biggest idols. Or at least, they got most of him.

Leonard Nimoy appeared in the form of a Spock action figure, but the venerable actor voiced the little figure in several dream sequences throughout the episode. It was all while Sheldon wrestled with whether or not to open and play with the vintage Transporter Room toy Penny had gotten for him in thanks for all the mooching she's done.

Eventually, he succumbed, but broke the action figure and quickly switched it for the one Penny bought Leonard. But a guilty conscience, in the form of Tiny Spock, convinced him to come clean, and after several, several, several lies, he finally did. Zap2It honored Nimoy by skipping the rating, instead giving the episode Spock's signature line.

Watch "The Big Bang Theory" every Thursday at 8 p.m. ET on CBS.

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