'Happy Endings' Finale: Meet the Missing Kerkovich Sister (Exclusive Photos)

Happy Endings Brooke - P 2013

Happy Endings Brooke - P 2013

Happy Endings' third season is coming to a close in just over a week -- and in what has now become a custom for the ABC comedy, it's heading into the hiatus with a wedding.

Alex (Elisha Cuthbert) and Jane's (Eliza Coupe) missing (and curiously never mentioned) sister, Brooke, makes her debut as the episode's bride. And The Hollywood Reporter has a first look at the bumpy nuptials and guest star Stephanie March (Law & Order: SVU).

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"The concept is that she out-Janes Jane," creator and executive producer David Caspe tells THR. "She's somebody that makes Jane become a babbling idiot. She's the big sister."

The lost Kerkovich sister is set to marry fellow guest star James Lesure (Men at Work) -- but as sopping wet photos and shocked facial expressions seem to imply, not everything goes according to plan.

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"She has so much presence," Caspe says of March. "And it turned out Eliza had always idolized Stephanie from watching her on Law & Order. So it was kind of a dream come true for Coupe to play against her. They were great together."

Happy Endings, which sees two rescheduled episodes air back-to-back this Friday, ends its season with another two episodes on May 3 at 8 p.m.