"The Last Ship" star Eric Dane

Since premiering in 2014, TNT's action-drama "The Last Ship" has been a roller-coaster of high-stakes missions, tumultuous political tensions and shocking acts of betrayal, and the series is expected to go out on a high note as its fifth and final season approaches its conclusion.

Based on the popular William Brinkley novel of the same name, the show follows the crew of a navy destroyer that is stuck at sea and unable to find a safe port after its crew learns that a virus has wiped out 80 per cent of Earth's population. What's ensued over five seasons is a fast-paced saga in which the crew attempted to gain intel on the state of the world and ultimately deliver a cure to the survivors. The penultimate episode of "The Last Ship" airs Sunday, Nov. 4, on TNT.

The show's unique setting and dire apocalyptic plot are what initially drew in many fans; the characters' isolation and limited knowledge of what's happening in the world make for a story that's rich in nail-biting tension. In an interview with Empire, executive producer and co-creator Steven Kane said that from the beginning of the project, he was "totally drawn to the idea of a crew and navy ship being the key to Earth's survival." Now in the last season, it seems as though the world is beginning to rebuild itself, but new and unexpected enemies have emerged for Commander Tom Chandler (Eric Dane, "Grey's Anatomy") and his crew, and this time they have to stave off a world war in the making. 

Since the series' genesis, when the crew of the USS Nathan James first learned about the Red Flu virus outbreak, the characters have been through a whirlwind of obstacles in their attempts to salvage humanity. Much of the first two seasons dealt with Center for Disease Control virologist Dr. Rachel Scott (Rhona Mitra, "Underworld: Rise of the Lycans," 2009) working on developing a vaccine for the virus, a plan that was compromised by the private interests of several antagonists, including a radical group of "Immunes" who wished to spread the plague and assert themselves as Earth's inheritors, as well as several world governments that attempted to use the plague as an opportunity for global political control.

After the assassination of Dr. Scott in the second season, Bridget Regan ("Jane the Virgin") was cast as the new female lead, playing former U.S. navy intelligence officer Sasha Cooper, who first encountered the crew of the Nathan James while under diplomatic cover in China. Sasha and her tactical force, Vulture Team, have been in the spotlight ever since.

The current fifth season is set five years after a cure was finally discovered and distributed. But what at first seemed to be a new era of prosperity for humanity has instead seen the emergence of new conflicts. In a way, the show has come full circle, with the old world being destroyed in a final battle with a devastating virus and the new world that's risen from the ashes of the old just beginning the opening moves of its own large-scale conflict. This season, Vulture Team was on an important mission in Panama when they were framed for an attack on the country's president, potentially sparking a new world war. It's a new world with new antagonists who have been raising the stakes and compromising the fate of humanity once again.

Bridget Regan in "The Last Ship"

Even within all the explosive action, the show's writers have still left room for more fluffy storylines in the final season, including a romantic one. When Sasha Cooper first joined the crew of the Nathan James, it was revealed that she and Tom Chandler had known each other before; one of the cliffhangers left dangling at the end of last season was the question of whether season 5 would see a more romantic relationship develop between them.

Of course, it isn't just the chemistry between the two leads that's kept "The Last Ship" on such a solid footing, with a strong cast helping to make the apocalyptic drama seem all too real. Vulture Team also includes Danny Green (Travis Van Winkle, "Friday the 13th," 2009), Wolf Taylor (Bren Foster, "Days of Our Lives") and Azima Kandie (Jodie Turner-Smith, "The Neon Demon," 2016), and as the final two episodes play out, bonds that have long held the team together are tested like never before.

The series has been an explosive enterprise from its very first scenes, and everything is coming to a head in its final hours. With millions of fans eager to see how the fate of the world pans out, the series can expect the kind of explosive send-off that's only fitting as it reaches its conclusion. Be sure to catch the final action firsthand as the penultimate episode of "The Last Ship," airs Sunday, Nov. 4, on TNT, followed by the thrilling series finale next week.