Gavin Casalegno, Lola Tung and Christopher Briney celebrate The Summer I Turned Pretty finale at the Prime Video photo call ...

The wildlife conservationist was just 15 when he and Fallon got into a staged — yet very convincing — backstage spat on The Tonight Show.

After months of waiting, it's almost time to say "Live from New York, it's Saturday Night!" And we finally know the details ...