Liverpool Sound and Vision Rating * * * *

Cast: Tom Baker, Mary Tamm, David Warner, Hayley Atwell, Jane Slavin, Toby Hadoke, Hugh Fraser, Nicholas Biggs, John Dorney, Beth Chalmers.

With The Lann about to destroy Earth as billions of the species mistake the planet as their own personal birthing pool, the second part of the two part story by Nicholas Briggs takes on one of those great sidesteps and gives fans something else to chew over and digest. Rather than the thought of interplanetary war between two species, the subtext offers something different, something not implemented in the Doctor Who world for a long while.