Michael has been a busy man since being fired from Tactical Response. Thanks to the squad's head honcho Kerry he's now undercover, and his job is to bring down the Raineys, a family team of cocaine importers. He sets up a buy-bust meeting in order to bring the Raineys down and coaxes Josh into becoming his wingman. The trade-off location changes at the last minute and whilst TR catches some of those responsible. Col Rainey has taken Michael and gone underground. Has his desire to prove himself to everyone put his life in serious danger? Meanwhile, Shannon finds herself face-to-face with her attacker.

The Tactical Response team continue their search for the man they believe is responsible for both the Police Minister and Michael's murders, as well as Josh's possible disappearance. They find out that he steals identities off people as a means of not being caught out, and Lawson has to make a big decision in order to catch him.

When an ex-newspaper editor causes a disturbance at Federation Square, Tactical Response tries to talk him down before he tragically falls to his death. A series of TAB robberies lead Tactical Response to link the incidents to a man attempting to settle a score. Meanwhile, struggling to deal with repercussions of the cyclist's death, Kerry leads Leon on a wild night out.

TR is given the responsibilty of protecting an underworld figure, who is testifying in court. A decoy is used, with an actor playing the man, but it goes downhill after the actor is shot dead. Serveral more attempts were made, and Kerry comes up with a unique way of protecting the man. Josh takes the man by himself, but is later cornered by the people trying to kill the underowrld figure. As they leave, TR shows up and the men are arrested. The episode ends with Micheal kissing Stella as she sleeps, and Kerry and Lawson having a conversation about the report on TR that Kerry wrote

After the assassination of the Victorian police minister, Kerry appoints a new task force, Cicero, in order to find those responsible. How will Lawson and the team react to new boss, Charlie Lewis?

Senior Constable Michael Sandrelli remains in intensive care whilst Tactical Response are left to pick up the pieces. Meanwhile, Shannon lets her emotional guard down.

As the bomb squad work to defuse a bomb, the team are tasked to fly to Fiji to extradite a South Korean National back to Australia. Shannon also responds to Lawson's marriage proposal, sort of.

Lawson is a part of a high speed chase involving a group of carjackers, Kerry is pulled over for drunk driving, and Josh, Grace and Michael are involved in a fatal car accident.

TR is called to a media centre, where a man has locked himself in a room and has planted a number of paint bombs throughout the building. Michael is hit, but not injured. Dom discovers where the bombs really are, and him and grace are both hospitalised after the explosions.

Lawson and Stella deal with a suicidal ex-footballer, Michael and Josh chase burglars through a series of complex tunnels, and Kerry is kept busy at the hospital where Dom and Grace are recovering. Grace unfortunately dies abruptly, while Connor confronts Josh after Grace revealed to him she was cheating on him with Josh.

As TR, along with the drug squad, work to catch a well known drug gang, Kerry's efforts to save Blake, a meth cook and reformed drug addict becomes personal when, devastatingly, she finds out that her son James is battling his own addiction. Meanwhile, Josh finds himself fighting for his life when an unknown man breaks into his apartment and tries to kill him.

The team finds a special way to honor their mate. Stella gives Lawson a hard time about not wanting to say anything at the funeral. Kerry is shocked when her son James is arrested for assault on a flight from Vietnam. When the car they are travelling in is run off the road, James sees the men in the other car and runs. Kerry and TR then find themselves in a race against time to save him from two violent drug runners.

Tactical Response goes into overdrive as they desperately try and to locate Michael after his undercover buy-bust goes horribly wrong. Josh starts to crumble under the guilt of letting Michael get away while Stella is furious, realising her best friend, and once lover, may not come back alive. It's a race against time as Kerry fights political red tape and the remaining members of Tactical Response do anything they can to get one of their team back safely.

Tactical Response attempt to find a sniper on the run, with an city under fire, the teams swiftly respond however struggle to find a reason for the gunman's actions.

TR score a lead when an ordinary civilian unwittingly implicates himself with Andrew Kronin's gang. As Lawson pushes the man to get to Kronin, Dom takes umbrage. Dom snaps, turning his gun on TR and flees. As TR 2 track down Dom, Lawson exults when he recovers a substantial amount of the heist money.

Tactical Respose race into town, on the hunt for Oliver Ginsberg. They learn that Ginsberg has placed a very large bomb under the city and that he has plenty more deadly tricks in store for them. Lawson finds himself in an awkward position when he must work with Dom, now a member of the bomb squad, to defuse the bomb.

Headstrong Kerry is dismissive of her own safety but when the threats are redirected to her son, her anger at the perpetrators can't be contained.

With a renegade Josh risking everything to find Michael's killer, the team finds themselves chasing one of their own and are forced to confront the question of how far they'll have to go to stop him.

The Tactical Response team becomes involved in stopping a weird hostage situation, meanwhile, Audrey discovers Michael slept with Stella in the aftermath of her miscarriage.

TR go bush for a routine training exercise. Unbeknownst to Lawson and Josh, the younger members of the squad soon find themselves at the mercy of Oliver Ginsberg, who has rigged the forest with deadly traps. When they discover Ginsberg is on his way to the city with a van full of explosives, they realize the worst is yet to come...

Josh's proposal to Tash is interrupted when ESD storm Tash's house and arrest him. Facing charges of corruption, Josh realises that his arrest is closely linked to the earlier attempt on his life, as he strives to clear his name once and for all.

Tragedy can have a profound effect on those involved. Everyone has different coping mechanisms, and Tactical Response continues to reel from a tragedy within their own ranks. Stella can barely build up strength to face the day and Christian appreciates a comforting presence from Amber. Josh, feeling responsible and immense guilt from what has happened, goes underground, deliberately avoiding contact from anyone at TR.

Tactical Response find themselves up against a carefully planned manoeuvre when Lawson and others are taken hostage by the Cuckoo as part of an escape attempt from a military courtroom. As part of the team negotiates for Lawson’s freedom, Josh and Stella follow their own investigation: searching for a bomb.

During a routine cell extraction Dom and Stella are caught in a prison siege. As Shannon negotiates with the ringleader, she slips up admitting Dom and Stella are inside. When the situation escalates Lawson sends in Josh and the riot police. Meanwhile an accident throws Kerry a massive curve ball.

As Lawson's growing obsession with the robbery crew threatens to pull Tactical Response apart, Josh shows his leadership as TR2 assist Drug Squad with the arrest of a drug importer. But things aren't as simple as they first seem when TR discover the offender's niece has been kidnapped and held to ransom. Josh must race to save the girl, in the process meeting her mother, Tash, who will change everything.