After assaulting a Drug Squad officer, undercover detective John Moreland faces suspension. He gets a second chance when Detective Sergeant Rebecca Ellis recruits Moreland and his team into her newly formed Covert Investigations Unit (C.I.U.). The C.I.U.'s first case is to take down David Thorpe, an elusive drug kingpin Moreland has been hunting for years. Rebecca's leadership and her fragile relationship with Moreland are severely tested when Thorpe suspects that Moreland is a cop.