The planet's unique biosphere is being exploited by an uncaring company
happy to rent out temporally isolated chunks of the planet to the highest bidder - no
questions asked. But the controlling computer seems to be malfunctioning, and the viablility
of the whole planet hangs in the balance - along with contless thousands of lives.
Arriving at Hirath's control base, the Doctor and Sam are soon seperated and trapped on the
dying planet. While Sam becomes the focus of attention in a barren penal settlement, the Doctor
discovers the secret of Hirath's unique condition - just as a race of hideous bloodthirsty alien creatures arrive in force to reclaim it.
Caught up in a desperate struggle for survival, it seems time has run out for every living creature
on Hirath - not least Sam and the Doctor...