Later that year, Fox hit the headlines again after she compared Bay to Hitler in a magazine interview.
She said of Bay in Wonderland magazine: "He's like Napoleon and he wants to create this insane, infamous mad-man reputation. He wants to be like Hitler on his sets, and he is. So he's a nightmare to work for, but when you get him away from set, and he's not in director mode, I kind of really enjoy his personality because he's so hopelessly awkward."
Adding, "He has no social skills at all. And it's endearing to watch him."
The actress was subsequently trashed by three anonymous members of the Transformers crew who published an open letter to her on Bay's website.
They branded her "dumb as a rock" and the "queen of talking trailer trash and posing like a porn star," as well as "grumpy" and "thankless, classless, graceless."
The post was later removed.
Fox was then booted from the franchise - although she claimed to have left of her own volition.
Bay later said that producer Steven Spielberg had ordered him to fire Fox over "you know, the Hitler thing".
He also said he wasn't hurt" by Fox's swipe. "Because I know that's just Megan. Megan loves to get a response. And she does it in kind of the wrong way. I'm sorry, Megan. I'm sorry I made you work 12 hours. I'm sorry that I'm making you show up on time. Movies are not always warm and fuzzy."
Bay did not say what role Fox would play in the Ninja Turtles reboot, but per The Hollywood Reporter, Fox will star as April O'Neil, a reporter and the crime-fighting turtles' human friend.
According to Reuters, Fox's agent has since confirmed that she's been cast in that particular role.
The Ninja Turtles movie is currently in the casting stage, THR notes, with turtles Donatello, Michelangelo, Leonardo and Raphael expected to be played by "relative unknowns", who will appear on the big screen via motion-capture techniques.
Last March, fans were up in arms about proposed changes to the mythology of the turtles.
Speaking at the annual Nickelodeon Upfront event in New York, Bay revealed plans to recast the crime-fighting superheroes as aliens.
"When you see this movie, kids are going to believe, one day, that these turtles actually do exist when we are done with this movie," Bay said during a presentation.
"These turtles are from an alien race, and they are going to be tough, edgy, funny and completely loveable."
The original back-story goes that the four turtles - Leonardo, Raphael, Michelangelo and Donatello - mutated into masked, pizza-loving crime-fighters after they were exposed to radioactive ooze in the New York sewers.
Fans cried foul over Bay's extraterrestrial revelation.
Bay responded to the backlash on his website.
"Fans need to take a breath, and chill. They have not read the script," he wrote.
"Our team is working closely with one of the original creators of Ninja Turtles to help expand and give a more complex back story. Relax, we are including everything that made you become fans in the first place. We are just building a richer world."
He was forced to speak out again in September 2012, when the internet was abuzz with the apparent leak of a first draft of the script for the movie.
"The leaked script for Ninja Turtles that different sites continue to comment on was written well before I, or anyone at Platinum Dunes, was involved with the project," Bay wrote.
"That script saw the shredder a long time ago. This is tired, old news - wait for the movie!"
Directed by Jonthan Liebesman (Wrath of the Titans), the film is set for release in May 2014.
FAST GOSSIP
And finally...
* Kanye West and Kim Kardashian reportedly having a baby girl. Couple said to be "over the moon". No confirmation from either of their reps yet.
* Donald Trump's Twitter "seriously hacked"; raunchy Lil Wayne lyrics posted.
* Hunger Games: Catching Fire Victory Tour posters revealed.
* Steven Tyler talks cocaine: "You could say I snorted half of Peru". Says he spent $5 million on drugs.
* Ethan Hawke says the Oscars are "asinine" and "dubious accolades"? Not so fast...
* Jermaine Jackson officially changes his last name to...
* MC Hammer arrested, claims he was a victim of racial profiling.
* Justin Bieber turned away from UK club because "he shuffles on stage".
* "I find it sickening" - Howard Stern defends Kelly Clarkson over Clive Davis' "degrading" attack in his memoir.
* Swatted: LAPD storms Clint Eastwood's home after prank emergency call.
* Turns out Lindsay Lohan is no match for a Pitbull.
* Backstreet Boys singer Nick Carter pops the question. Check out the engagement bling.
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- Rumour Has It