The Bluestone 42 team are called out on routine ops with their CIA liaison officer Carter, where things take a drastic turn. Back at base, they are introduced to Mary, the new padre, who Nick, the Ammunition Technical Officer, takes an instant shine to. Meanwhile, Simon grapples with Millsy over the report that Nick has forced him to write on his behalf, and the young Privates - Mac and Rocket - enjoy winding up Bird who may or may not have named the bomb seeking robot 'Arthur'.

Nick has grown tired of eating the same food every day and is desperate to find something tastier. Mary encourages Nick to let Millsy run a re-training exercise. Millsy is ecstatic and ensures he does a very thorough job, much to the disdain of the team.

After Bluestone 42 join a midnight raid on a bomb factory and rescue a kidnapped Danish aid worker, they find more than they bargained for. Simon tries to get a book deal for his memoir.

Mary reveals a secret about her past before she became a padre and Nick tries to take full advantage. Bird is offered a promotion.

Nick tries to prove to the padre that he is not superstitious. Simon tries to earn respect by joining in dangerous homemade games with Mac and Rocket.

Nick and Simon help each other to learn to dance, whilst the arrival of vet Parikh reveals Bird as a terrible flirt.

A mortar attack on the patrol base sends Bluestone 42 diving for cover.

Nick faces a challenge with a booby-trapped car bomb. Simon stands up to his fiancée.