Josh Radnor Ted Mosby Actor Jason Segel Marshall Erikson Actor Neil Patrick Harris Barney Stinson Actor Alyson Hannigan Lily Aldrin Actor Cobie Smulders Robin Sherbatsky Actor Bob Saget Narrator David Henrie Son Guest Star Lyndsy Fonseca Daughter Guest Star Enrique Iglesias Gael Guest Star Mandy Moore Amy Guest Star Amanda Loncar Lydia Guest Star Frank Alvarez Steve Guest Star Donovan Dustin Tyler Guest Star Carter Bays Executive Producer, Writer Craig Thomas Executive Producer, Writer Pamela Fryman Director