KEY POINTS:
They say comedy is the hardest form of acting but if anyone's a natural, it's Alyson Hannigan.
"I learned quickly as a child that if I could make my mom laugh instead of yell at me it was much better," she says. "That probably was the defining moment of my life. I was an only child, so I was always going to be the one in trouble, y'know? I didn't have any siblings to blame stuff on or be compared to."
Hannigan is best known for her role on Buffy the Vampire Slayer, playing Buffy's computer-hacking best mate, Willow Rosenberg. But hearing her voice on the line from LA is enough to bring back awkward memories of one particularly prurient time at band camp in American Pie.
It would be too much to call her dizzy, although Hannigan's wobbly pitch, girlish laugh and tendency to keep talking over the questions makes this feel just like a conversation with Michelle.
Today though, she's discussing her latest role, as Lily on How I Met Your Mother. So much for the death of sitcom. It's Hannigan and her lesser known co-stars who are having the last laugh. HIMYM is doing well in the United States, with steady ratings and favourable reviews.
Billed as "a love story in reverse", the show pivots on a narrator (Bob Saget) from the future telling his kids the story of how their parents met. Flashback to find Ted at 27, hating being single, particularly because his best mate Marshall has just proposed to his girlfriend of nine years, Lily. Although the show plays with time and has a few unpredictable twists, it's an old-fashioned, multiple-camera, laugh-track sitcom.
Lily is a pretty grown-up role for someone who personifies youth. Hannigan is nearly 33 but she speaks like a teenager. So far, her roles have appealed mainly to a young audience.
"I just go with my instincts and what I respond to. I don't want to be on a show that I wouldn't watch or what I wouldn't enjoy. You never know what anything's going to turn into. I mean we had no idea about Buffy. It could have been totally cheesy or weird. But it wasn't."
Hannigan is constantly amazed at the show's lifespan, thanks to DVDs and word of mouth. She got the role of Lily because the show's producers were big Buffy fans. And people still approach her to spout that infamous line from the Pie films.
"It's really incredible to be a part of a franchise that is still on people's minds. Yes, there have been times when it has been awkward hearing it when someone came up to me. Like, I kinda wish they didn't say it when I'm with my mother-in-law. But I wouldn't trade the experience for anything. When you're exhausted or whatever or they're shouting at you, it's a little weird. But that's okay."
Hannigan waded through many scripts, a lot of them "crap", to get the role she wanted.
"I knew I wanted to do a half-hour, I wanted to do comedy. This one just stood out. It was just miles better than everything else I'd been reading. What really touched me was that it has heart and it wasn't just, 'Oh, we're going to just try to make you laugh really hard for half an hour'. I really cared about the characters. Each character had an individual voice which I think is pretty rare."
Still happily married to her former Buffy co-star Alexis Denisof, who she wed in 2003, Hannigan also responded strongly to the Lily-Marshall relationship. The TV couple have just got engaged.
"I love being part of a healthy relationship on television, which you don't see a lot of, particularly with all the reality shows on. Even though they've been together forever and they're taking this next step, it really is a new relationship because there are still things they have to deal with and learn about each other.
"Yes, they've been together for nine years but they're kids now growing up into this more mature relationship. I just love that you see them and you can't picture them with anybody else."
The same could be said of her spouse but Hannigan says the on-screen couple is nothing like her real-life relationship.
"Alexis and I were both older when we met and had already gone through the weird issues you have to go through in discovering a new relationship, so I feel like ours is the adult version of theirs.
"Some of the stuff they go through after being together for nine years I'm like, 'Really?' Because that was like month three for Alexis and me. I sort of feel like they're the toddlers and we're the grown-ups."
Even if she doesn't sound that way.
LOWDOWN
Who: Alyson Hannigan, who plays Lily Aldrin on How I Met Your Mother.
Born: March 24, 1974
Key roles: Willow Rosenberg on Buffy the Vampire Slayer (1997-2003), and its spin-off, Angel, (2001-2003), Michelle Flaherty in the three American Pie films, (1999-2003), Trina Echolls on Veronica Mars, (2005), Date Movie, (2006).
See it: How I Met Your Mother, Saturdays, 8pm, TV3
