The images show the tireless optimist that Emmet searches the galaxy for Lucy, also known as Wyldstyle, (played by Elizabeth Banks) after her abduction by a malevolent alien force. The super-confident Rex saves Emmett's life after it drifts into a meteor shower.
Rex introduces himself: "The name is Rex Dangervest! – Archaeologist defender of the galaxy, cowboy and raptor trainer!
Pratt has played all those characters in "Guardians of the Galaxy", "The Magnificent Seven" and "Jurassic World", respectively. He agrees to help Emmet save Lucy, but warns him about going to the Sis-Star System, ruled by Queen Watevra Wa-Nabi of Tiffany Haddish.
"You do not want to go anywhere near the Sis-Star System! It's ruled by an alien queen, only the hardest will come out alive!" Rex warns.
Other characters include Will Arnett as Batman, Channing Tatum as Superman, Jonah Hill as Green Lantern and "Brooklyn Nine-Nine" student Stephanie Beatriz as Sweet Mayhem. Mike Mitchell directed the film, while Phil Lord and Christopher Miller produced and co-wrote the film with the creator of "BoJack Horseman", Raphael Bob-Waksberg.
Warner Bros. opens "The Lego Movie 2: The Second Part" on February 8.