Marshal vows to ruin Barney and Robin's big day while Ted appears to be not getting over his feelings for Robin.
"Someone is going to ruin this wedding," Robin says in a promo of "How I Met Your Mother" season 9. Barney adds, "It's just a question of who." Declaring in a plane, "I'm gonna ruin this wedding," Marshal is an obvious suspect, but Lily has a strong reason why she should be suspicious of Ted's every move.
Ted, seemingly still not getting over his feelings for Robin, takes a road trip with Lily to Long Island to attend the wedding. In a clip for the premiere episode, Lily gets frustrated after Ted refuses to speed up the car.
"HIMYM" will kick off its ninth and final season on Monday, September 23 at 8 P.M. ET/PT with two half-hour episodes. In the first part, Robin and Barney come across a startling family discovery on their way to Long Island for their wedding weekend. Meanwhile, Marshall sees something online that changes the course of his entire journey back east, and Lily confronts Ted about letting go of Robin.
Later in the second part, when James reveals that he is getting divorced, Robin worries about how Barney will take the news. Marshall races to find a way to get to New York in time for the wedding, and Ted deals with being alone at a romantic hotel.
The last chapter of the sitcom will wrap up the big story arc of how Ted meets the titular mother. Cristin Milioti joins the show as a series regular after she was first introduced as the titular mother in the season 8 finale.
Meanwhile, "True Blood" star Anna Camp has just been cast as one of the most attractive, available unfortunate guests at the wedding. She replaces "The Office" alumna Ellie Kemper, who was initially tapped for the role.
"How I Met Your Mother" final season promo:
"How I Met Your Mother" 9.01 clip:
"How I Met Your Mother" 9.01 photos: