Fresh off one of its best episodes this season, How I Met Your Mother has announced an exciting piece of casting news.

Peter Gallagher - forever Sandy Cohen to OC fans, currently starring on Covert Affairs - will stop by a December episode of the CBS sitcom as Professor Vinick, the man Ted always wanted to impress at Wesleyan University.

According to TV Guide Magazine, Gallagher's installment will likely air on December 17 and it will find Ted once again aiming to make his mentor proud. But it won't be easy.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.