War and romance collide in the sweltering heat and political unrest of 1960's Aden, - a port city in today's Yemen - where the British Royal Military Police battle local militia in an intense struggle to control the strategically important port. The officers know only too well that a lapse in luck or judgment risks death. But do they know what their wives are risking at the local country club, where the swinging '60s are in full swing?

The team scrambles to make sense of the disintegration of the unit. The unit reunites to rescue Mack and clear their names. Nerve gas is stolen and the team is sent to retrieve it. Jonas tests his daughter's strength and conviction when she decides to enlist. The team deals with a loss and Jonas vows revenge.

Denise and Frank fight to save their marriage; while Claudia Joy discovers a life-changing personal truth of her own. Newly promoted Joan wrestles with a major decision that will affect her husband and new baby; while Roland imagines what his life would be like had he taken a different path. Pamela questions Chase's family commitment after he returns from capture; and Roxy encounters unexpected new responsiblities as Trevor explores a new job in the...