The Doctor is still being jolted through his own timeline, and has now found himself with Nyssa, Tegan and Adric in ninth century Iceland near a Viking settlement on the edge of a volcano. A settlement whose leader has just found a god in the ice. The TARDIS crew are soon in a battle with the fearsome Ice Warriors. There are a lot of lives to save...and not just those of their new friends. The Doctor's about to find that his biggest battle may be with his own conscience.
—Big Finish Productions