While Ecklie fights for his life after his shooting, Russell's patience begins to wear thin as the team tries to get to his kidnapped granddaughter before she is killed.
The Gathering will centre around a violent attack on a teenage girl during a rave on a tidal islet. Set on Merseyside, the drama focuses on a group of teens from disparate backgrounds, each of whom could have committed the crime, along with their parents - who give equal cause for suspicion.
