NSYNC to Reunite for New Song in Movie "Trolls Band Together"

Is Trolls Band Together about to reunite one of the greatest US boy bands of all time?

After the trailer for the upcoming animated film -- the third installment in DreamWorks' Trolls franchise -- hinted at a boy band reunion storyline for Justin Timberlake's character, Branch.

A source exclusively tells ET, "JC Chasez, Lance Bass, Joey Fatone and Chris Kirkpatrick are expected to have surprise roles in the third Trolls film, Trolls Band Together, with Justin Timberlake."

The source added that the quintet will also reunite as *NSYNC to release a new song for the movie -- their first song together since 2001's "Girlfriend."

The Trolls Band Together trailer does seem to tease the connection between Branch's character and Timberlake's real-life boy band past, revealing that Branch and his four brothers -- played by Troye Sivan, Kid Cudi, Daveed Diggs and Eric André -- were once in a band called BroZone.

When one brother, Floyd (Sivan), is kidnapped, John Dory (André) tracks Branch down to reunite the group and save their brother.

"Branch, we’re out of sync," Floyd tells his brother in a flashback included in the trailer, making more hints at the boy band connections.

"We've gone from boys to men, and now there's only one direction for us to go: to the back streets."