The Broadway star and Billie Eilish's brother teamed up to perform the song
He may be best known as an actor - both on Broadway and in films like 'Pitch Perfect' and TV shows like 'The Politician' - but Ben Platt has also released his own music, too.
The LA man released his debut album 'Sing to Me Instead' last year and the bonus edition of the album featured a song written by none other than one Finneas O'Connell.
So it was only right that he enlisted Finneas for an 'isolation' edition of the song, 'So Will I' - which he's now releasing as a single - as performed on James Corden's show last night.
The pair joined forces from their respective homes, with Finneas on piano, and the result was something pretty special.
Watch it below: