The cat-and-mouse chase to bust a gang who enrolled at Swansea university in order to sell drugs to students. Plus a twisted case of revenge. Why did a man who was attacked with a machete in Cardiff refuse to cooperate with the police? When a shooting happens on the streets, detectives finally find a link, but, bizarrely, it takes a visit to the x-ray department of the local hospital to finally find the unusual hiding place for the gun.