The Lone Gunman

"The Lone Gunman" is the fourth episode of the first season of Australia S-Unit. It was written and directed by Daniel Isaac and introduced the character Brad Fisher, portrayed by Jas Singh.

Story
Three months after Marcus' supposed death, Derek, after being forced to take time off work, decides to go looking for Mr Greene. As he leaves to go look for clues of his enemy's whereabouts, Brad Fisher arrives at Marcus' house and says he's been assigned to be Derek's new partner and help him locate Mr Greene. Derek reluctently agrees and sets Brad up in the house.

Derek follows a lead on a murder which brings him face to face with one of Greene's employees, David Wren. Wren accepts arrest and goes to the S-Unit HQ. Derek returns home to Brad and asks if there are any leads. Brad subtly asks Derek if he and Greene know each other and if Derek is working with Greene. Derek exclaims he is not and that Greene is just messing with him. Brad then reveals to Derek after finding evidence that Greene is a consulting criminal and crime lord who sponsors criminals to act on their crimes. After this revelation, Derek calls Carol, Marcus' sister, and apologises for "killing her brother."

Derek then pursues another lead at a house where a murder has taken place. Returning home once again to Brad, Derek discusses more about Greene. Brad leaves and Derek hears a gunshot from outside. Derek sees an assassin, essentially sent by Greene, to kill Derek. Derek hides in the house and waits for the assassin to enter. Once he does gunfire opens and Derek remains in cover. WHen the fire stops, Derek walks slowly in the direction of the assassin but is knocked in the face. The two have a fist fight in which the assassin gains the upper hand and prepares to kill Derek.

Derek is saved however by Marcus, who reveals himself to still be alive. Derek runs outside to see if Brad is alright, and he is. He then leaves Derek and Marcus to reunite. Inside Marcus explains that he was placed into witness protection and went under cover as soon as he was supposably killed. Marcus was under cover in one of Greene's drug warehouses in order to learn more about Greene. Greene soon learned Marcus was under cover and sent the assassin after Derek. Upon learning this, Marcus returned to Derek to save him. Marcus then reveals to Derek that he has the current location of Mr Lucas Greene and that it is time to arrest him.

Derek agrees and the two race to the car and drive toward Greene's location.

Reception
The Lone Gunman received positive reviews, with viewers calling it a step up from "Gone with the Wind". It was praised for the twist of Marcus' return and the cliffhanger ending.