Well, the show has finally been cancelled, and it's no wonder. The writers apparently had one thought, what would happen if a nuclear submarine with the power to wipe out most of the planet went rogue? Nothing bad with the concept, but then they fell short to create a plausible scenario and properly develop the story. Instead, we are left with spaghetti plot inconsistencies that insult viewer's intelligence (assuming fans of this show are as such).
The purpose of protocol on a nuclear ballistic submarine is to follow orders and fire without hesitation once the correct codes are provided. This is the reason POTUS (President of the United States) carries what's referred to as "The Football" (missile launch codes) everywhere he goes. Imagine what could happen if a confirmed nuclear ICBM from North Korea is in flight to a US target and an order to fireon enemy launch sites is disobeyed simply because the crew is not sure what's going on and has second thoughts about starting WWIII.
Of course, the show is poor fiction and may be appealing to some. My exception is to the blatant anti-American theme; the tag line being "Honor in Defiance" as if it would be acceptable as patriotic for an officer to disobey firing orders. The U.S. government is portrayed as corrupt at the highest levels, with only the mutineers standing against them. In later episodes, even communist China is painted as a reasonable, benevolent country offering needed supplies, seemingly in exchange for nothing. When the Chinese envoy offers the captain a board game as a gift, the captain comments "Chess is more my game", to which the envoy replies "Chess is a game where you destroy your enemy, my game is to gain territory with minimum losses". In yet another exchange the captain; "I swore an oath to my country, not necessarily my government", with the envoy replying "One reflects on the other".
Indeed, the show gets more ridiculous with every episode; the nuclear explosion from the missile launched in the first episode detonating in the water "200" miles east of Washington DC and clearly visible from the ground in New York, over the horizon and 200 miles away. By the way, there are more than 100 miles from DC to the Atlantic Ocean, with Delaware in between. The launch key getting stolen, a Chinese envoys offering assistance, members of the seal team sneaking out of the island (and then return) in order to rescue a wife held in the Philippines, floggings, the local island thugs torturingofficers with little consequence.... I could go on and on.