Battle of Zaruthstra
From Tardis Wiki, the free Doctor Who reference
The Battle of Zaruthstra was a conflict which involved the human race and took place in the year 4037. The disgraced Sontaran Commander Strax acted as a nurse, tending to those wounded in battle. The Doctor's TARDIS landed there to summon Strax, who owed him a debt, to help in his mission to rescue Amy Pond and her baby at Demon's Run. (TV: A Good Man Goes to War)