Casey Wilson and Ken Marino Casey Wilson and Ken Marino

On NBC's upcoming comedy Marry Me, Happy Endings star Casey Wilson will trade in single girl Penny for Annie, a woman who's been in a steady six-year relationship with Jake (Ken Marino). "Annie is slightly less desperate than Penny," Wilson said at the Television Critics Association fall previews on Sunday. "I'll try to do subtle difference between the characters. Annie doesn't always act like Penny."

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That does not mean, however, that Annie will be any less manic than Penny. In the pilot alone, she goes on such a long, single-minded rant about Jake not proposing to her that she misses the fact that Jake is indeed, trying to propose... and even has a surprise party waiting in the wings to witness her meltdown. (Get a sneak peek here.)

This consistently cuckoo quality between the two characters could be owed to the fact that they're inspired by Wilson herself. Marry Me creator David Caspe, who also created Happy Endings, loosely bases his new comedy on his real-life romance and marriage to Wilson. "Casey is very capable of screaming at me when I'm doing something nice for her," he revealed. Later, Wilson said that even though she never followed through, at one point she was so angry at Caspe that she thought it was entirely rational to drive her car into their house.

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Don't expect Annie to get all the crazy though. As her partner, Jake has his share of moments, especially when the inevitable wedding needs to be planned. "I assume we'll explore the male side of it as well. Going off the rails is not just for ladies anymore," Marino said and added. "I was excited to play this part because lately I've been playing a lot of d---s."

Marry Me, which premieres Tuesday, Oct. 14 at 9/8c on NBC, also stars Tim Meadows, JoBeth Williams, Dan Bukatinsky, Sarah Wright, Tymberlee Hill and John Gemberling.

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