Mary Lynn Rajskub, Patrick Fischler

24 alum Mary Lynn Rajskub and Lost's Patrick Fischler will guest-star on the penultimate episode of Grey's Anatomy's eighth season, TVLine reports.

Rajskub and Fischler will play a couple who checks in to Seattle Grace after they begin experiencing strange symptoms while on a honeymoon. The episode will air May 10.

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Rajskub, who recently appeared on CBS' now-defunct How to Be a Gentleman , is best known for her role as Chloe on 24.

Aside from his role on Lost, Fischler has appeared on Mad Men, Curb Your Enthusiasm, Californication and Body of Proof.