It's 1983 and there's a sinking submarine and something in the cargo...

The Doctor and Clara land on a damaged Russian Submarine in 1983 as it spirals out of control into the ocean depths. An alien creature is loose on board, having escaped from a block of Arctic ice. With tempers flaring and a cargo of nuclear weapons on board, it’s not just the crew but the whole of humanity at stake!

What did you think of this episode and the return of The Ice Warriors?