Transformers: Drift Series by Shane McCarthy, Casey Coller

It's all out war in Philadelphia, as Optimus Prime and the rest of the Autobots roll out to stop Starscream and his forces from killing Sam Witwicky! The biggest, most explosive battle in Transformers history begins here! The fate of the universe rests on the outcome and the action of this summer's hottest movie heats up right here!

DRIFT RETURNS! After leaving the Autobots in disgrace, he's now alone, on a mission to clean up the darkest depths of the galaxy - until Ratchet shows up to try to bring him home!