Justin Timberlake Appears at 'Trolls' Premiere with *NSYNC

Justin Timberlake showed face for the first time since Britney Spears' explosive memoir claims -- and he did so alongside some of the people who love him most ... his wife included.

The singer attended the 'Trolls' premiere in L.A. Wednesday with none other than Jessica Biel right by his side ... smiling wide and putting on a united front with her hubby. They were holding hands in front of cameras, and their power-couple presence was certainly felt.

Ditto for JT and his ex-boy band members ... who were also there on the carpet. Indeed, all the *NSYNC guys attended as well -- and they, too, got together for some group pics.

We broke the story ... *NSYNC put together a last-minute plan to show up to this event, seeing how their flick is coming out this weekend -- and the studio wanted to do some 11th-hour press to plug the movie ... this after the SAG-AFTRA strike recently came to an end.

Time will tell if them touching down in the flesh affects box office numbers, but the bigger takeaway here is Justin ... seeing how his name got dropped a lot last month by his ex.

As we reported ... a lot of "truths" came out about him in Britney's book -- including the fact that she had an abortion while they were together, which she said he pushed for at the time. She also alleged he'd cheated during their relationship ... among lots of other claims.

The dude took heat in the Twitter-sphere -- and he never came out and addressed any of it himself ... opting to lay low instead. Now, he's surfacing with the missus looking cheery.