HOW I MET YOUR MOTHER “Do I Know You” (S4E01) Season Premiere September 12, 2008 How I Met Your Mother Check out some pictures from HOW I MET YOUR MOTHER‘s fourth season premiere episode, “Do I Know You” airing this Monday, Sept. 22 (8:30-9:00 PM, ET/PT) on CBS. I cannot wait to see what Barney (Neil Patrick Harris) has in store for us this season . I wonder how they are going to deal with the story line. It would be funny to see Barney in a committed relationship. Did I say funny? I meant to say Legen….Wait for it….dary. You can see more photos from How I Met Your Mother “Do I Know You” below. Read all our How I Met Your Mother coverage here. Episode Synopsis: As Stella responds to Ted’s (Josh Radnor) proposal, Barney (Neil Patrick Harris) realizes that he’s in love with Robin (Cobie Smulders), on the fourth season premiere of How I Met Your Mother. (Photos: Eric McCandless) Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on Reddit (Opens in new window)Click to share on Google+ (Opens in new window)Click to share on Tumblr (Opens in new window)Click to share on Pocket (Opens in new window)