From CBS' official press release:

Robin and Ted discover that they get along better as roommates if they become 'friends with benefits,' on How I Met Your Mother, MONDAY, JANUARY 12.

Heidi Montag and Spencer Pratt (The Hills), Play Playmate Kendra Wilkinson (The Girls Next Door) and Kim Kardashian (Keeping Up With the Kardashians) Guest Star

When Ted and Robin become “friends with benefits” to deal with conflicts they're having around the apartment, Barney tries to resolve the issues so they'll stop hooking up.  Meanwhile, “reality” stars get too real for Marshall when they taunt him from the pages of his magazine, on How I Met Your Mother, Monday, January 12 (8:30-9pm, ET) on the CBS Television Network.

How I Met Your Mother stars Josh Radnor as Ted, Jason Segel as Marshall, Neil Patrick Harris as Barney, Alyson Hannigan as Lily, and Cobie Smulders as Robin.


Source: CBS
(Image courtesy of CBS)