The first trailer for the upcoming Transformers spin-off focused on fan-favorite Autobot Bumblebee is coming tomorrow. A video on the Transformers official German Facebook account sees actor John Cena appear on-set, teasing a trailer release for tomorrow.

"This is John Cena from the new movie Bumblebee," Cena said, in-costume as the mysterious Agent Burns. "We are taking it back to the beginning with Bee, and it's set in a time period where I first fell in love with Transformers. The new trailer debuts tomorrow. And don't miss Bumblebee in theaters this Christmas."

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Set in 1987, the solo prequel to the Transformers live action film series follows the iconic yellow Autobot as he takes refuge in a California junkyard. Found by teenager Charlie Watson (Hailee Steinfeld), the duo quickly bond as they find themselves targeted by Decepticons.

Cena was cast as Agent Burns in the film in July. While details about his character are still being kept under wraps, Burns is believed to be working for Sector Seven, a covert government organization founded to handle extraterrestrial threats.

Directed by Travis Knight (Kubo and the Two Strings) from a script by Christina Hodson, Bumblebee stars Hailee Steinfeld, Jorge Lendeborg Jr., Pamela Adlon, Jason Drucker, Abby Quinn, Rachel Crow, Ricardo Hoyos and Gracie Dzienny. The film is scheduled to open on Dec. 21.