Spied: Transformers 4 cast on set!

Check out our behind-the-scenes look into the upcoming Transformers movie.

Our spy photographers typically camp out at General Motors' Milford Proving Grounds with the hope of spotting the latest prototype vehicles, but today they were treated to a surprise when they discovered the automotive cast of the next Transformers movie.

Of course Optimus Prime will make a return for the fourth installment of the Transformers franchise, but our spy shots reveal a few new characters are set to make their silver screen debut.

The typical Bumblebee Camaro will be included in the Transformers 4 cast, but the character looks to be in line for an update. The rear of the car spotted on set sports the same basic updates that graced the tail of the 2014 Camaro Z/28, but the front of the car appears to have a unique treatment. We can almost guarantee that Chevrolet will eventually offer a Transformers-themed 2014 Camaro to the general public.

A 2014 Chevrolet Corvette Stingray, Bugatti Grand Sport Vitesse and a Medium Tactical Vehicle from Oshkosh Defense were also spotted on set.

A number of other vehicles were also on hand for the filming - including a Chrysler 300 and a Pontiac Solstice - but it remains unclear if those vehicles are merely extras or will actually play some role in the movie.

Look for Transformers 4 to hit theaters next summer.

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