'How I Met Your Mother': Peter Gallagher will torment Ted

"How I Met Your Mother" will offer a window into why Ted is the way he is when it comes to architecture, and that window will look exactly like Peter Gallagher.

The former "O.C." and current "Covert Affairs" star will guest in an upcoming episode of "How I Met Your Mother" as Ted's (Josh Radnor) aloof college architecture professor, TV Guide reports. The episode will feature flashbacks to the gang's college years as well as a present-day story featuring the professor, whose approval Ted still craves.

Gallagher is best known for his drama work, but he has his comedy bona fides as well. Sandy Cohen on "The O.C." had more than his share of funny material, and Gallagher has also guested on "Californication" and "Whitney" in recent years.

His "How I Met Your Mother" episode is scheduled for mid-December.