'How I Met Your Mother' Star Open to 'How I Met Your Father' Crossover

How I Met Your Father has already made plenty of allusions to its predecessor, How I Met Your Mother, but it hasn't featured an appearance by star Josh Radnor yet. Radnor played the central character Ted Mosby on the sitcom from 2005 to 2014, and in a new interview with Newsweek he discussed his scant involvement with the sequel series now airing on Hulu. He said that he hasn't been asked to appear on the show yet, but he would love to do so if it ever fits the story.

"I had a really sweet email exchange with Hilary Duff," Radnor revealed. "We kind of went back and forth about being the 'I' on How I Met Your dot dot dot... [Hilary] has said publicly she'd love to have me on, so I wouldn't turn down an invitation." Radnor's character was the titular storyteller on How I Met Your Mother, but he didn't do the narration. He played Ted on screen while Bob Saget narrated as Ted in the future, telling these stories to his future kids.

How I Met Your Father has a similar setup – not to mention plenty of shared set pieces. Duff plays Sophie, a hopeless romantic living in New York City and hoping to find true love in the bleak dating world. She is telling her love story to her children in the year 2050, and her future narration is done by Kim Cattrall. Sophie's best friends live in the Manhattan apartment that was the most consistent setting on How I Met Your Mother, situated above McLaren's Pub in the same building.

How I Met Your Father has already had four notable appearances by characters from the original series. Of course, Cobie Smulders made a cameo as her old character Robin Scherbatsky, and the door is open for more with her. We also saw Kyle MacLachlan as "The Captain" and Laura Bell Bundy as his wife, Becky. Finally, Joe Nieves has reprised his role as Carl, a bartender who is apparently still working at McLaren's.

Still, How I Met Your Father risks a lot by employing too many call-backs, Easter eggs and references. The show could easily become incomprehensible to new fans, or even existing fans who don't have a meticulous memory for the original series. On top of that, the ending of How I Met Your Mother was not universally beloved, with many critics saying it tried too hard to surprise fans in the end. How I Met Your Father could tip its hand if it's not careful.

How I Met Your Mother is streaming now on Hulu and Amazon Prime Video. How I Met Your Father Season 1 is streaming now on Hulu, and Season 2 is slated to premiere on Tuesday, Jan. 24.