Part of How I Met Your Mother featuring Josh Radnor, Jason Segel, Neil Patrick Harris, Cobie Smulders, and Cristin Milioti.
Rise to Fame
Willow Rosenberg started as Buffy's sweet, bookish sidekick and ended as the character who nearly destroyed the world. Playing that arc from 1997 to 2003 gave Hannigan more range than most TV actors see in a full career. American Pie in 1999 made her name outside genre circles. The band camp line was the kind of punchline that gets quoted out of context for a decade, which is its own kind of staying power.
In the Spotlight
Two defining TV roles (Buffy the Vampire Slayer and How I Met Your Mother) would set most careers up for decades. Hannigan's post-HIMYM chapter has been quieter than that suggests. She hosted Penn & Teller: Fool Us from 2016 to 2023 and competed on Dancing with the Stars in 2023. The public image stayed remarkably clean throughout. No tabloid spirals, no feuds. Whether the low-drama decade reflects contentment or caution, she hasn't said.
Side Notes
When she asked out her Buffy co-star Alexis Denisof, he turned her down. Didn't want to date a colleague. They stayed friends, he eventually confessed he'd developed feelings, and they married in 2003. Their first daughter, Satyana, was born on March 24, 2009, Hannigan's own birthday. Her X handle is @alydenisof, using his name while keeping Hannigan professionally. The rejection took years to resolve, which makes it a better story than most things she's ever been cast in.