The BBC have released the synopsis for the series 8 opener, Deep Breath. The time is still to be confirmed, but it can be expected around Wednesday.

When the Doctor arrives in Victorian London, he finds a dinosaur rampant in the Thames and a spate of deadly spontaneous combustions.
Who is the new Doctor and will Clara’s friendship survive as they embark on a terrifying mission into the heart of an alien conspiracy? The Doctor has changed. It’s time you knew him.