Greg and Agnes meet an eccentric old woman living on her own, called Mrs. Butterworth, who is expecting a visit from some traders called Millar and Mackintosh. She tells a bemused Greg that she was recently raided by 'Red Indians', who came from Marbury.
The traders are at Marbury school where they are doing business with a boy called Eagle. He is after some seed potatoes. Eagle warns them not to tell anyone about the school, as the community there is made up entirely of children.
Jenny has met a man called Mr. Oliver and asks him about Greg's whereabouts. He tells her he hasn't seen him.
Greg promises Mrs. Butterworth that he will check out her 'Red Indians' for her. Agnes remains behind with her. Neither she or Mrs. Butterworth is too pleased about the arrangement.
At the school, one of the boys threatens to tell the traders about the problems they are having. Eagle stops him. There is a girl screaming in pain upstairs.
The traders leave the school with one of the boys in tow. Meanwhile, Mr. Oliver advises Jenny to seek out the traders, Millar and Mackintosh, as they may know of Greg's whereabouts.
At Mrs. Butterworth's house, the traders have arrived and are keeping the old woman and Agnes busy talking, whilst the boy who accompanied them steals some of her chickens. The traders give her some cabbages and then leave.
On his way to the school, Greg spots an 'early warning' trip-wire across the road. In the school's sick bay the girl is getting worse. One of the boy insists that she needs medical attention and tells Eagle that he is worried as so many of them are now going down with the illness. Eagle cannot see what can be done. He is warned about Greg's arrival.
Greg asks the children who have gathered outside where all the grown ups are. Eagle threatens Greg and the children conspire to hang Greg up the leg from a nearby tree branch.
Eagle threatens Greg some more and tells him that there are no adults there and furthermore that he is in charge. Meanwhile, Agnes and Mrs. Butterworth are plucking chickens whilst they await Greg's return.
Near Marbury, Jenny has met up with Millar and Mackintosh who lie and claim not to have heard of Greg. They suggest she stay with them for a while.
Eagle checks on the sick girl who is called Libbie and soon after relates to another boy called Phillip that her finger dropped off in his hand. Phillip is certain they need help, especially given the number of other cases. Eagle is concerned that the adults would just take over again. Instead he is determined to distract the community from worry about the disease.
Millar and Mackintosh send Jenny on to see Mrs. Butterworth having claimed to remember Greg after all. Greg meanwhile is still tied up and at Eagle's mercy. Eagle orders that his shoes be removed and announces that they will hunt him. He gives him a head start.
Eagle gives Greg a head start. Meanwhile Millar and Mackintosh tell Jenny that they got the impression that Greg was 'with' Agnes. They also tell her that she and the children [John, Lizzie and baby Paul] are welcome to come and stay with them.
Greg is hunted by the children who are armed with bows and arrows and even guns.
He narrowly avoids being shot by one of the older boys and continues to run on.
He takes a stumble down a bank and catches his foot in a trap. A young girl finds him and sends the hunting pack off in the other direction.
Greg happens upon one of the boys who is showing signs of the disease. He is shaking and delirious. Meanwhile, Jenny has lost her way.
The hunt is over and Eagle has decided to show Greg the dormitory containing all the sick children. Greg has no idea what disease has taken hold. He is taken to see Libbie who is now very quiet. He decides to get Agnes and Mrs. Butterworth to come to the school as the latter used to be a nurse.
Agnes and Mrs. Butterworth are brought to the school. Mrs. Butterworth thinks Libbie has gangrene which has reached an irreversible stage. Greg tells Eagle that Libbie will die.
Mrs. Buttterworth suggests that there is one thing they can do for Libbie. Jenny finds her way to Mrs. Butterworth's house, but finding no-one there settles down for the night.
Eagle sleeps at Libbie's beside until Greg takes over. With Eagle gone, Greg puts her out of her misery by suffocating her with a pillow.
In the morning Greg tells Eagle that Libbie died in her sleep. Eagle reveals that she was his sister.
Jenny leaves Mrs. Butterworths. Eagle explains to Greg why he doesn't want to be abused by adults again, as he was both before and after the death. He tells Greg that they have founded a good settlement that works.
Returning home with Agnes, Mrs. Butterworth is sure someone has been there whilst they've been away. Meanwhile, Eagle tells Greg about their dealings with the traders.
Back at the school again Agnes and Mrs. Butterworth discuss possible causes of the disease with Greg. Greg is put in mind of the mystery of the Marie Celeste. One of the explanations for the disappearance of the crew was that there had been fungus on the rye that had been used to make the bread which made them go mad. Eagle tells Greg that Libbie made bread from rye provided by the traders, and that not everyone ate it as they didn't like it. This explains why some people have become ill and others have remained untouched.
In medieval times the disease was known as St. Anthony's Fire [the incorrect name for ergotism]. Greg asks Eagle to get everyone to gather all the sick together with musical instruments for them to play. Agnes and Mrs. Butterworth are confused by his request. The sick children begin to march and play. According to Greg this sort of activity had been used before as it was said to sooth the effects of the disease.
Millar and Mackintosh learn that they sold fungal rye to the community and Greg arrives to take them back to the school to face Eagle. Jenny arrives just after they have left.
Eagle meanwhile has gone off with the children to a nearby civil defence centre which they called 'the outpost', for guns and food. Millar and Mackintosh tell Greg that the place was mined during the emergency of the death...
Greg rides off and it seems at first that he is too late to save them. However the children are unharmed despite the explosions. Eagle informs the traders that they will work off the debt they owe to them for selling them the rye.
Greg tells Agnes to go back to Whitecross and says he will follow on later. Their plans are interrupted by the discovery in a nearby field of an elephant living wild.
Eagle and the children agree to let it roam wild, even though someone is likely to shoot it in the future. A horse rider is spotted on the horizon. It is Jenny, but Greg doesn't know this, merely commenting that they look familiar.
This is Ian McCulloch's second script for the show and he has often cited it as misdirected, due to the spoiling of plot surprises. However, the episode's main problem and indeed the problem with the entire final series is the frustrating 'ships in the night' theme, which painfully separates Jenny and Greg. In this episode this plotting is taken to almost farcical extremes which becomes increasingly difficult to excuse as different parties miss each other by seconds. Its interesting that one of...