The Doctor has lost, his ageless enemy reigns supreme, and a shadow is falling over creation. Nothing can stop the devastation… except, perhaps, one woman.

The Doctor and UNIT investigate Ruby’s past. But as the Time Window reveals horrifying secrets from Christmas Eve, the mysterious Triad Technology unleash the greatest evil of all.

Landing on the Welsh coast, the Doctor and Ruby embark on the strangest journey of their lives. In a rain-lashed pub, the locals sit in fear of ancient legends coming…