The BBC has released the official story synopsis for The Pilot, the opening episode of Series 10:

Two worlds collide when the Doctor meets Bill. A chance encounter with a girl with a star in her eye leads to a terrifying chase across time and space. Bill’s mind is opened to a Universe that is bigger and more exciting than she could possibly have imagined – but who is the Doctor, and what is his secret mission with Nardole on Earth?

It airs Saturday 15 April on BBC One, with the time to be confirmed next week.

New teaser: