Robin comes face to face with an old foe

Part one of two. Robin and his men learn that Isabella is raising an army for Prince John and she's already taken the men from two villages - Locksley is next. The outlaws thwart the Sheriff's plans by driving off her henchman, Blamire, and his soldiers, and lead Loxley's men into Sherwood.

Now, Robin decides his only course is to take Nottingham Castle and hold it until King Richard's imminent return. Fortunately, Guy knows of a secret tunnel that will take them to the castle's heart.

Meanwhile, Isabella spreads mistrust among the outlaws, announcing that Allan a Dale is pardoned for his 'services to the Sheriff'. Robin no longer trusts him and leaves him tied at their camp, but Allan escapes and comes face to face with an old foe...

Archer becomes aware of the secret tunnel and tries to win favour with Isabella, offering to trap Robin and Guy in return for a hefty reward. He devises a mechanism, which traps Robin, Guy and Muck underground - and their tunnel prison is slowly filled with lime.

Tuck and Little John, supported by the men of Locksley, arrive at the castle gate and peacefully block the path of the supply train Isabella is sending to Prince John. Blamire can't kill the innocent men but Isabella forces a guard to strike at Kate. This is too much for Archer who hurls a blade, killing the guard, and the men storm into the castle.

Archer grabs Kate and heads for the tunnel, releasing the gasping outlaws. They return to Nottingham and confront a captured Isabella, but Allan's dead body has been delivered to the gate and, as they look up, they see an army advancing on them. It's led by Vasey, the former Sheriff of Nottingham - he's alive and he wants his town back!