Roger Bart Roger Bart

Revenge's Roger Bart will guest-star on the upcoming final season of How I Met Your Mother, has learned.

Bart will play an employee at the hotel in Farhampton where Barney (Neil Patrick Harris) and Robin (Cobie Smulders) are set to tie the knot sometime this season. It is currently unclear how many episodes he will appear in.

9 teases for How I Met Your Mother's final season

The Tony winner is best known for his roles as journalist Mason Treadwell on Revenge and as crazed killer pharmacist George Williams on Desperate Housewives. Last year, he also appeared on Law & Order: SVU and Political Animals.

How I Met Your Mother returns on Monday, Sept. 23 at 8/7c on CBS.

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