The Transformers movies can't all be robots hitting each other, no matter how much Michael Bay might enjoy conjuring that up. Nope, they need humans, and Transformers: The Last Knight has, according to Mashable, added a key one in the shape of Liam Garrigan.
While nothing has been officially confirmed about the plot, rumours have swirled that it will feature King Arthur and Merlin in some capacity (the sight of Optimus Prime with a ruddy great sword again have helped fuel that). With Santiago Cabrera already cast as the magician, Garrigan is playing King Arthur. He's got form on that front, having played the character in TV's Once Upon A Time. So maybe he already has his own chainmail.
The Last Knight, in addition to returning some of the usual Autobots and Decepticons has the living likes of Mark Wahlberg, Josh Duhamel, Tyrese Gibson, Isabela Moner, Laura Haddock, Jerrod Carmichael, Gil Birmingham and Anthony Hopkins. Bay is busy shooting (and blowing things up) now and the movie will arrive on June 23 next year.