Doctor Who: Rutans vs Sontarans: Rendition

At the edge of the Sontaran-Rutan War, a large medical ship lingers in space. The Doctor and his friends find a group of strange survivors aboard planning something unusual to save their commander.
What new powers do the Rutans possess? What secrets does the Lockhart hold? As the conflict creeps closer, the Doctor must work out how to rescue those no longer versed in war...