Martin is on edge as he awaits the arrival of the incinerator. It turns up over 20 minutes late but when it comes he can't contain his excitement. However, the chosen spot for the incinerator doesn't meet with Martin's approval, and Holly loses patience as Martin becomes increasingly short-tempered. Tanya and the girls plan to make a protest in their PE lesson.

Togger comes to school with a black eye. Everyone noticesbut he refuses to talk about it. Abel lets slip his dad might be responsible; his classmates become concerned he is being knocked around. Jeremy agrees to investigate further and corners Togger. He admits his dad landed one on him after getting caught speeding - he'd got points on his license which could jeopardise his job as a trucker. Mr McDonnell is installed as adjudicator for G-1; precluding any further sabotage from Chloe. The Wannabees realise they'll have to come up with their own ideas for the enterprise scheme and, after rejecting a string of ideas from Andrea, Chloe suggests haircuts. Unfortunately she lets slip mum cut her hair, which Andrea finds highly amusing!

The incinerator gives Max an idea. During games, he steals Donnie's bag and throws it in the incinerator. Donnie is predictably furious - his new sports kit was in there! Martin can think about nothing but the incinerator in class. He tells Holly winning is important because once he left school, it would show people that he could do something. The girls turn up for PE wearing ankle-length skirts - to make the point the school has a Victorian attitude towards PE kits. Mr McDonnell is furious; Tanya pulls out her student handbook to remind him the rules didn't specify a length for PE skirts. Mr McDonnell is fast losing patience when Mrs Bassinger arrives, but before she can intervene, red smoke is spotted coming from the incinerator.

Grange Hill is evacuated as smoke pours through the building. Mrs Bassinger is once again forced to end school early. Martin insists this wouldn't have happened if the incinerator was placed where he suggested, and it looks like the end for the project. Wally is cleaning out the machine when Holly spots the remains of Donnie's sports kit - problem solved! Mrs Bassinger allows the project to continue with Wally's supervision.

Year 10 rally around Togger, urging him to tell someone about his black eye - or they would. Togger promptly changes his story, saying he got the shiner by running into a lamp post. No-one is convinced.