At Locksley village, Robin intervenes in preventing the villagers from exacting justice on a man who has been setting alight churches and poisoning wells. Recognising the man is a soldier from King Richard's army, Robin takes him back to Sherwood Forest; the man is unresponsive to questioning, but the gang notice he has strange eastern symbols tattooed on his chest. Robin and Much empathise with the man, who they recognise as suffering PTSD (or 'Crusader's sickness' as they call it) and Robin puts Much in charge of taking care of him.
Meanwhile in Nottingham, Sheriff Vaisey, irritated by Guy's mooning over Marian after their previous disagreement, just tells him to buy her something to make her warmer towards him again. Their conversation is interrupted by one of the guards, who informs the Sheriff his Saracen guest is expecting him for dinner. Gisborne is disdainful at the Sheriff entertaining a Saracen, but Vaisey replies they need to at least make the pretence of keeping him happy to get what they want.
Back in Sherwood, Will and Allan bring the gang to an unexpected find; a massive wagon left abandoned in the forest. Will notes the level of craftsmanship that went into making it; whoever owns it is clearly rich, not from around these parts and heading for the castle. Suddenly, John sees something inside it that scares the living daylights out of him; Robin finds the item in question- a strange mask made of metal and covered in spines- and briefly uses it to scare the others. John and Allan are quickly convinced the mask is an object of black magic and the wagon belongs to a sorcerer.
At Knighton, Gisborne appears to have taken the Sheriff's advice, gifting Marian with an impressive horse as a means of reconciliation. At the outlaws' camp, Much is trying to get through to their new guest (who he has dubbed Harold) by involving him in cooking dinner for the gang, but when the others return to the camp and hand over the strange mask to Djaq in the hope she might know what it is, Harold turns violent, holding a knife to her throat and babbling about Saracen evil; John quickly knocks him out with a well placed rock. Back at the castle, the Sheriff is forced to dine with a well dressed Saracen, who pushes the Sheriff to arrange the peace negotiations; Vaisey assures the Saracen he is doing all he can to ensure Prince John's arrival at Nottingham.
With Harold trussed up in a makeshift cage and John terrified of the mask and who its owner might be, Robin pays Marian a visit; although she is sceptical of the gang's belief a sorcerer has taken up residence in Nottingham Castle, she agrees to try and find out who the Sheriff's mystery guest is. Back at camp, Much tries to calm Harold down, noting that he and Robin share Harold's horrific memories of the battles fought out in the Holy Land; Much tries to free Harold from the cage, but he refuses, insisting it's safer for everyone, revealing he was tortured into madness by Saracen fanatics, the same ones who left the markings on him. At Nottingham Castle, the Saracen guest requests some of the Sheriff's men to help him retrieve his wagon; Vaisey reluctantly agrees, and sends him off with Gisborne and a patrol. Unfortunately, when they get to the wagon, Robin and co turn it into an ambush, absconding with the newcomer as a hostage.
Back at the outlaws' camp, an astounded Djaq gives the newcomer an identity; Prince Malik, nephew of Saladin himself. Malik explains that the mask is not an instrument of sorcery, but a medical tool for a practice similar to acupuncture. Malik explains that the mask was part of a peace embassy he was bringing to Prince John in a bid to bring an end to the fighting in the Holy Land; Robin tries to convince Malik Prince John and the Sheriff have no interest in honouring his wishes, but Malik insists he has to try and requests they release him.
Back at the castle, Gisborne and Vaisey quickly fall into recriminations over whose fault it is Malik has gone missing, when much to their surprise, the prince walks back into the courtyard unharmed. The gang conclude from intel Marian provides that Malik is being treated like he's an ambassador, when he's in truth a hostage, and the Sheriff and Gisborne are expecting a hefty ransom. In the forest, they come across a party of Saracen women seemingly transporting said ransom, but Djaq stops them from trying to steal it, insisting the women are in truth Saladin's finest assassins. The gang are initially sceptical...but quickly change their tune when they see what the women can do. They initially assume this is a rescue mission to free Malik, but Djaq points out the illogic of sending assassins for that. Robin then works out that the assassins have come to kill Malik; he may want peace, but he's come to England against his uncle's orders to negotiate a peace deal Saladin will have no interest in. Back at the castle, Vaisey has finally gotten tired of playing the gracious host, and when Malik brings up the accusations Robin made about him, the Sheriff has Gisborne throw the Prince in the dungeons. When Harold reveals that the warrior women were the ones responsible for his torture, Robin declares they have to try and save Malik if there's to be hope of an end to the fighting.
The women arrive at the castle; after the Sheriff grudgingly presents Malik to them, their commander hands over the key to the chest holding the ransom; unfortunately it doesn't contain treasure but a smoke bomb, which quickly incapacitates the guards present, before the warrior women unleash their lethal skills. Gisborne and Vaisey are the only survivors (Gisborne by playing dead, Vaisey by flinging luckless guards in the path of blades meant for him). Outside the chamber, the assassins' commander tries to kill Vaisey, only to be cut down by Robin. Realising his best chance of staying alive is by following the outlaws, Vaisey follows them to the great hall where Malik is being kept, ordering his guards to slow the assassins down.
The guards barely slow the assassins down, who storm the great hall and a vicious battle breaks out between the outlaws and the warrior women, who quickly outmatch Robin and his men. Before the battle is lost, Harold storms to the rescue, cutting down his former tormentors. With the day saved, Vaisey angrily orders Malik out of Nottingham and reminds Robin that it's "business as usual tomorrow".
Back in the forest, Malik uses the mask to try and help Harold, who admits it does help a little. He offers to accompany Malik back to the Holy Land to keep him safe, noting that he won't have peace until the fighting out there is brought to an end, while Malik notes that his survival should help convince his uncle that the will of Allah is towards peace. After they depart, Robin congratulates Much on how much good his care and patience did for Harold.
- Ain't Too Proud to Beg: Vaisey willingly hands over Malik's location in an attempt to save his own life. It doesn't work, but Robin saves him in the nick of time.
- All Girls Like Ponies: Invoked: Gisborne buys Marian a magnificent horse as a reconciliation present after their fallout in the previous episode.
- Amazon Brigade: Saladin's assassins.
- Being Tortured Makes You Evil: Implied with Harold.
- Curb-Stomp Battle: Saladin's assassins easily carve through Vaisey's guards. They're then on the receiving end when Harold charges in to save the outlaws.
- Dramatic Wind: One of these blows up after Robin starts messing around with the mask and the gang insist it's an object of dark magic.John: Robin, leave it be!Robin: John, it's only a mask! [At that point, a massive wind blows up and birds fly in all directions] Oh come on! Get a grip.
- Enemy Mine: Vaisey tags along with the outlaws because he recognises they're his best chance of staying alive, even ordering his men to obey them.Robin: [to the guards around Malik] Forget about us, watch the entrance!Vaisey: [bringing up the rear] YOU HEARD HIM! GUARD THE DOORS!Much: [surprised] The Sheriff's with us?!
- Failed a Spot Check: Gisborne and Vaisey really should have noticed Prince Malik did not look pleased to see his alleged rescuers.
- From Bad to Worse: From Vaisey's perspective: he's saved from a murderous Saracen assassin...only to be then confronted by half a dozen pissed off outlaws.
- Love Makes You Dumb: Humorously invoked by Vaisey while berating Gisborne for losing Malik.Gisborne: You ordered me to take him into the forest!Vaisey: You were supposed to bring him back!Gisborne: Alright, I will find him somehow!Vaisey: A ransom requires a hostage! What am I supposed to give them?! YOU?! How much do you get for love-struck idiots these days?!
- Magic Mushroom: Marian accuses the gang of indulging in these when she sees the mask.
- Mass "Oh, Crap!": The outlaws when they see what the assassins can do.Will Scarlet: That's not worship...that's target practice.
- Also during the final battle when everyone hears the screaming from Vaisey's guards trying to stop the assassins falls silent.
- My Friends... and Zoidberg: Vaisey tags along with the outlaws for the final battle and Robin incorporates him into their plans to protect Malik. Vaisey is surprised by this, but Robin points out it's the only way they're getting out of this alive.
- Oh, Crap!:
Vaisey: [running after Robin and the others] DON'T LEAVE ME!
- Vaisey and Gisborne when they see the treasure chest they just opened contains a smoke bomb, and then it goes off...
- Vaisey when he sees the assassins coming straight for him.
- Shell-Shocked Veteran: Both Robin and Much recognise Harold as this, as like him, they've both suffered from Crusader's sickness (A medieval euphemism for PTSD).
- Status Quo Is God: At the end of the episode, Vaisey reminds Robin they're back to being enemies again the next day after their brief alliance against the assassins.Vaisey: Get him, Prince Bismallah far away from here!Prince Malik: The feeling is mutual.Vaisey: And Locksley, remember! Business as usual, tomorrow.Robin: I look forward to it.
- Title Drop: From Vaisey to Prince Malik after he finally has enough of playing the gracious host and decides to drop the Affably Evil act.Vaisey: Two words. Peace? Off! Throw him in the dungeon!