Boyden and Tait attend a fight at Harvey Wallace comprehensive and discover that one or two of the pupils are acting strangely around their teacher, Sonia Graham. While Tait is smitten, Boyden discovers that rumours are escalating that Sonia is having extra-marital relations with some of her students. Meanwhile, Ashton and Buxton attend a fire at a public convenience, and find two young girls trapped in the toilet cubicle. When Ashton manages to free them from danger, they both make good their escape and Ashton suspects that something is wrong. Glaze and Webb attend a shooting at a local gymnasium, where they find that none of the witnesses are willing to offer any information. (thetvdb.com)