- You may be looking for the unrelated novel.
Beltempest was a Provost-Major at the Imperial Landsknechte headquarters on Purgatory. The real Beltempest killed himself due to a post-hypnotic command implanted to prevent him revealing information. An undercover agent posed as Beltempest, to find out who was behind the effort to kill the Seventh Doctor and Benny. (PROSE: Original Sin)