Captain Arthur Pendragon has put together the best team of specialists that the SAS has ever seen, but when his superiors assign Lieutenant Merlin Emrys as his communications officer, Arthur does everything to make him feel unwelcome. Arthur's job is to protect and guide his team through dangerous missions, and he worries that he can't do that when the newest member has a mysterious background and acts suspicious when he thinks no one is looking.
As their assignments become more dangerous, Merlin can't help but to use his magic to keep his team -- even his prat of a Captain -- safe from threats they couldn't possibly understand. But when they are sent on a undercover operation against a group of zealots intent on a magical apocalypse, Merlin needs to confront his fear of discovery and derision, and to finally trust his team with his secret.
Arthur and Merlin rely on each other for more than the sake of their mission. The entire world is at stake. When they learn -- from dragons, no less -- that they are prophesied to restore the balance of magic to the world, they fight on regardless of the outcome, because duty, honour and loyalty is a far stronger driving force than destiny.