FX has released an eclectic first trailer for Legion, a new X-Men series from Marvel. Though the trailer doesn't make Legion's X-Men connection perfectly clear — and, honestly, I'm not sure what this trailer does make clear, since it's bouncing all over the place in terms of events and imagery — it does start to show its main character's mutant powers. He's just not totally aware he has them yet, leading to some explosive results.
The show follows a character named David Haller, who comic fans know as the mutant Legion. This series seems to be starting off with Legion's origin story, letting Haller discover the world of mutants and then become part of it. The series starts sometime in 2017. Another X-Men TV series is also in the works for Fox.