Bay let the cat out of the bag on his site with the simple phrase: TMNT: we are bringing Megan Fox back into the family!

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Sources say Fox and Bay reconciled over a series of recent meetings and that one tete-a-tete that won her over was with director Jonathan Liebesman, who wowed her with the storyboards, according to insiders. (Bay is not directing the movie but producing it via his Platinum Dunes partners Brad Fuller and Andrew Form.)

The movie is in the casting stage and last week was testing actors, mostly relative unknowns, for the roles of the Ninjas – Leonardo, Michelangelo, Donatello, and Raphael – which will be motion-captured.

Fox, repped by ICM, starred in Bay’s first two Transformers movies before on-set friction and public comments led to her being written out of 2011's Transformers: Dark of the Moon.