As the promos for the episode had already revealed, that train is where the Mother met Lily Aldrin (Alyson Hannigan), one of the closest friends of the Mother’s future husband Ted Mosby (Josh Radnor). In an interview with BuzzFeed last month, Milioti said the episode, titled “The Locket,” was a blur for her, but not for the reason you may expect. Best known for her Tony-nominated role in the Broadway musical Once, the 28 year old hadn’t really watched HIMYM until executive producers Carter Bays and Craig Thomas cast her in the role last March — and then she promptly spent her summer binge-watching all eight seasons. So while Hannigan and the crew were thrilled to finally get to work with the Mother, she had a different reaction to her first real day on set in July. “It’s so weird,” she said with a laugh. “I think they were like, Oh my god, this is a scene with the Mother! But for me, I’m like, Oh, I’m getting a scene with Lily! It’s so different for me!”
Milioti, a New Jersey-native and professed die-hard New Yorker, noted that the biggest revelation for her in the scene was how clean the train was. “That’s a way clean Metro North car,” she said. “There were no beer bottles or urine rolling up and down the aisles. Yeah, Metro North is not a good place to be.” (For the geography sticklers among you, since Farhampton is a totally made-up place, the Metro North train could totally go there.)
Read more at Buzzfeed