Three rookie police officers in Northern Ireland must survive their probation period. The odds are at least one of them isn't going to last.The team quickly find themselves fighting drug gangs, paramilitaries, undercover operatives, the local community and even their own force in a battle for justice. Working as first responders, they're brought into direct contact with characters from all walks of life. Most of the people the cops encounter just need a helping hand to live a better life. But when a large-scale investigation into a local criminal gang is quickly shut down, difficult and dangerous questions surface. Who is protecting these criminals? And why?