Doctor Who: Zygon Hunt

On the jungle planet Garros, Earth Forces Knight Commander-in-Chief Greg Saraton and his team are hunting gigantic beasts, for sport. When the Doctor and Leela arrive, they are caught up in a web of intrigue where there is no clear friend or foe. What is Saraton's vital connection with Earth's Solar System's Defence Shield? Why are the giant reptilian birds of Garros attacking? What terrible secret lurks deep within the trees? Before the truth can be revealed, a heavy price will be extracted and loyalties will be tested to the limit.