Per all accounts, the cast of "10 Things" grew incredibly close during the production of the film. As Joseph Gordon-Levitt shared, "...we had such a good time. All of us hung out, all the time" (via Insider).
Naturally, when Ledger passed away, it was difficult for the cast to process; they would later go on to discuss how much Ledger brought to his role (via USA Today). When asked by "Watch What Happens Live" host Andy Cohen what her favorite memory of shooting the film with Ledger was, Stiles revealed it was when they filmed the memorable scene wherein Patrick serenades Kat with "Can't Take My Eyes off You" from the bleachers. "'My favorite memory of that day – the whole day, was just phenomenal," Stiles said (via the Daily Mail). "'I mean, like, running up and down those stadium steps and nobody knew he had this amazing voice. He just went full out and I got to watch it."
The idea to sing that specific song actually came from Ledger himself; initially, the writers were between "I Think I Love You" by the Partridge Family or "I Touch Myself" by the Divinyls. Ledger even had specific ideas about what his character should wear for the scene (via Insider).
While, sadly, Ledger only had a limited time to make these films, his personality and talent shone through.
