Matthew Rhys Admits Keri Had to Teach Him Who Mister Rogers Was For A Beautiful Day In Neighborhood

Talk about a very important lesson!

"The Americans" star Matthew Rhys was up for quite the role when he was handed the script for "A Beautiful Day in the Neighborhood," the movie inspired by the real-life friendship of Fred Rogers (a.k.a. "Mister Rogers") and Tom Junod, the Esquire journalist who profiled him — and was forever changed by it.

But! Before he could get the role, there was something very important he had to do: Learn who Mister Rogers was in the first place.

"I wasn't aware [of who Mister Rogers was, growing up in Wales], and I'm sadder for it," Matthew tells Rachael. "I think we're a poorer nation for not having Fred Rogers, but unfortunately, he didn't make it across the Atlantic.”

Which meant that getting the "Beautiful Day" script was the first time he'd heard of the TV icon — ever!

"The script came to me, and I said to Keri [Russell], 'Who's Fred Rogers?'" At which point he hilariously imitated his longtime partner's gigantic gasp and astonished, "Get out!"

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"But unbeknown to me, she said, 'Fred Rogers is in our living room, because our two-and-a-half year old is watching 'Daniel Tiger's Neighborhood,'" he says — which, as he notes, is the animated spinoff of Rogers' long-running PBS program.

A pretty adorable introduction to Mister Rogers, if we do say so ourselves.

And speaking of, who is playing the legend himself? Well, that would be none other than Tom Hanks, a choice that is, as Matthew says, an example of perfect casting.

"I've said this before, but [the casting] couldn't have been better," says Matthew. "They're almost one in the same entity. America's dad is playing America's dad."

Our hearts!

Watch the video above for more from Matthew on working with Tom and what he feels made Mister Rogers so special.