The war between the Sontarans and the Rutans has been going on for millennia. And is likely to continue for millennia more. A terrible conflict with no care for consequences or collateral damage. Billions have died with no end in sight. The Brigadier is used to the Doctor acting strangely, but this time there's something decidedly different about the whole affair. As he looks into the Time Lord's odd activities outside of UNIT, there's a mystery that'll take Lethbridge-Stewart to a site very familiar to Sarah Jane Smith. Can the Brigadier trust his old friend? Who are his new mysterious allies? And is the future of humanity really at stake? A Sontaran threat could spell the end of their long-standing friendship... and the entire planet!

CAST: Tim Treloar (The Doctor), Sadie Miller (Sarah Jane Smith), Jon Culshaw (Brigadier Lethbridge-Stewart), Jeremy Ang Jones (Stanley), Nicholas Boulton (Captain Saint), Lucy Goldie (Sergeant Moss). Other parts played by members of the cast.