Hannah John-Kamen stars in "Killjoys"

When "Killjoys" premiered in the summer of 2015, the show's exciting premise -- bounty hunters in space -- instantly clicked with hordes of fans who saw untapped potential for thrilling world-building and darkly seductive action. Four years later, the intergalactic drama has proven that it not only has an attractive veneer, but it boasts richly engaging plotlines, internal politics and characters. The Canadian series has established a name for itself in the world of sci-fi television lore. The keenly anticipated fifth and final season of "Killjoys" premieres Friday, July 19, on Syfy.

The Guardian reviewed the first season of the show and proclaimed it "a sexy dollop of fun just right for 'Firefly' fans." That's really saying something, as the short-lived "Firefly" has become something of a cult classic and cultural phenomenon. The heroes of "Killjoys," played by Hannah John-Kamen ("Ready Player One," 2018), Aaron Ashmore ("Smallville") and Luke Macfarlane ("Brothers & Sisters"), strike a familiar note for "Firefly" fans -- they're living at the edge of the law, and while they profess to be disengaged from the world around them, they often end up stepping in to save the day.

The show follows the exploits of Dutch (John-Kamen), Johnny (Ashmore) and D'avin (Macfarlane), three "Killjoys" (or bounty hunters) living dangerously as operatives for the Reclamation Apprehension Coalition (RAC). The organization is an independent entity in the J Star Cluster, whose agents are to remain politically neutral and have no outside affiliations, living under the rule of the motto "the warrant is all." Ruthlessly capable when it comes to their inglorious profession, the trio takes on a series of jobs -- warrants and hits -- for various private clients.

Any science fiction worth its salt will quickly branch out from the established premise and evolve. "Killjoys" does that exceptionally well. By the fourth season, all the unexpected threats, moral dilemmas and outside players with their own darker and grander motives have taken the characters on an unexpected ride. The rich world that the series has built adds incredible depth to the storylines, but even that takes a back seat to the tales of its heroes' humanity.

The Killjoys have thus far encountered galactic corporate overlords, a hive-mind species of humans called the Hullen, and a sinister RAC sleeper-agent project coded Red 17. Plus, they've been embroiled in the violent class wars of the planetary Quad where their story takes place. With all this character development, the stars of the series have really excelled, but John-Kamen stands out for her portrayal of two different characters: Dutch turns out to be the creation of a Hullen clone named Aneela. After the truth of Dutch's existence was revealed in Season 3, the two characters formed a bond and united against a mysterious common enemy: The Lady. This entity continues to be a main source of galactic upheaval and is sure to play a major role in the fifth and final season.

Aaron Ashmore as seen in "Killjoys"

In an article for Den of Geek, Dave Vitagliano wrote that "whenever a show employs the 'dueling twins' approach, a number of traps and pitfalls lie in wait, ready to snag lazy writers." Yet fans and critics seem to agree that the shared character arc of Dutch and Aneela has been an entirely original and well-crafted plotline, and John-Kamen is often praised for her believable portrayal of two completely different characters whose stories are deeply entwined.

John-Kamen, who has also recently starred in "Ant-Man and the Wasp" (2018), talked to Brief Take about her success and what draws her to her roles: "I think that with each character I get, it's always character and story driven, and that's what entices me into a project." She also divulged that "it's especially fun to do sci-fi ... that's the inner child in me." That leaves her right at home in her "Killjoys" role, where reality is totally suspended in the name of breathless drama and explosive action.

With so much attention devoted to the huge scale of the "Killjoys" universe, the show has been praised for also managing to keep up witty banter and create emotionally believable connections between characters. At DragonCon 2018, Ashmore addressed fan curiosity about the relationship between Johnny and Zeph (Kelly McCormack, "That's My DJ"), a Hullen scientist working with the heroes. "I think they respect each other now ... Zeph is biological and John is more technical, and there's room for everybody," he said, noting that the writing of the show is filled with enough other intricate drama that there isn't much time for side relationships, yet it still makes room for the details that add a depth of humanity to the script.

There has been much fanfare surrounding the buildup to the final season of this sci-fi series. Experience the beginning of the end when Season 5 of "Killjoys" premieres Friday, July 19, on Syfy.