Katie Holmes makes a guest appearance on How I Met Your Mother on October 31 to celebrate Halloween with the cast.
In the October 31 episode, Ted finally tracks down the girl in the Slutty Pumpkin costume and discovers that her name is Naomi. The duo head back to the rooftop party where they first met.
Meanwhile, the group attends a Halloween party where Ted comes as a 'hanging chad', Barney comes as Uncle Sam and Robin makes a nod to her Canadian heritage by dressing up as a Vancouver hockey player.
Barney is also shocked to learn that he is part Canadian and Lily suffers from "pregnancy brain". Other guest stars for the episode include Christine Pickles as Rita and Jack Walsh as Morris.
To view photos for the October 31 episode of How I Met Your Mother, click the arrows above.