It's a fairly routine romp of a futuristic bank being raided by aliens, a concept recently done much better in Naomi Alderman's Eleventh Doctor novel Borrowed Time, but it's fun anyway. I have a feeling that the story of the Second Doctor encountering the shark-like Selachians here isn't quite consistent with that in the two novels which feature them, but as they are all by Steve Lyons I won't let it worry me too much. ( )