LISA O'CONNOR/AFP via Getty Beanie Feldstein and Ben Plat
Platt, 27, recounted the way he asked Feldstein, 28, to prom and the special significance it has today during an appearance on The Tonight Show Starring Jimmy Fallon on Wednesday night.
"We were best friends in high school and we were prom dates and my favorite part about that now is that when I asked her to prom I sent her flowers and I wrote a little card that said … Beanie loves Funny Girl, which for those who don't know she's going to star in Funny Girl on Broadway this year, which is wild," the Dear Evan Hansen star said. "I always knew she loved Funny Girl so [the card] said, 'Don't rain on my parade. Please come to prom with me.' "
He smiled as he added, "And now she's Fanny Brice."
Platt went on to discuss how he and Feldstein each had goals to be cast on Broadway and are now living out their dreams.
"We were big theater nerds together. We starred in all the musicals together in high school and it was always our dream," the actor told Jimmy Fallon.
In another sweet anecdote about their friendship, Platt shared, "She actually … for my 16th birthday she gave me little cufflinks and she gave me a little note that I have saved that said, 'Wear these when you win your first Tony.' and I did. I wore them at Radio City."
Platt won a Tony Award in 2017 for best performance by a leading actor in a musical for his titular role in Dear Evan Hansen.
ben platt/ instagram Ben Platt and Beanie Feldstein
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Feldstein has previously described her relationship with Platt as a "soulmate connection."
"What I can say is that I think what Ben and I have is beyond friendship, honestly," she told Broadway.com last year. "It's like a soulmate connection."
The actress added, "We're like twins separated at birth or something."