Black Sea (2015) took a ragtag crew of sailors, English and Russian, stuffed them into a rusty old submarine, and sent them on a hunt for millions of dollars of Nazi gold lost in an old sunken U-boat. It's a nice premise for a heist movie, but that's not what Black Sea is as much as it's an attempted character study. As one would expect, the hotheaded bunch of men are endlessly at odds with one another, for personal and cultural reasons that stem from each man not fitting into the ebb and flow of capitalist living. From the start, it’s obvious that the same number of chaps who set out on the journey aren’t coming back. This isn't Ocean's Eleven (2001), where everyone has an identity. There are simply too many indistinguishable characters at the start, most meandering about the sub as expendable setpieces. The few who demand attention are the ones instigating all the drama - and if Black Sea is anything, it’s a Lord of the Flies-esque drama about a bunch of grumpy career sailors willing to do anything for more than their fair share of the loot.
Too often, the motivations of the film’s characters are contrived beyond reason. They murder each other and engage in shouting matches seemingly out of nowhere, then carry on with things as if nothing happened. The most frustrating example of this is the flaky character of Fraser (Ben Mendelsohn). While Mendelsohn’s acting is mostly fine, Fraser is massively inconsistent, his actions more or less dictated by the needs of the plot to overcome its next hurdle. While it’s clear he thinks the British on board deserve more of the gold than the Russians (for some reason), that motivation doesn’t transition into the choices he makes throughout the film.
“There are moments when the script leans too heavily on "because I said so" storytelling, pushing the plot to wherever it needs to go without coming up with a way to make it seem as though it's getting there organically. (The psycho Fraser is particularly irritating in this regard; he's at the center of so many sudden, horrendous crises that it makes you think less of Robinson for being reckless enough to hire him.)” - Matt Zoller Seitz, RogerEbert.com
Fraser is the first to kill another crewman, stabbing him in the stomach because, well, he didn't like the guy. As the wounded man stumbles from the attack, he does something that triggers an explosion which not only kills more men, but damages the submarine. Fraser is a through-and-through psychopath (Jude Law’s character Robinson even says so when introducing the crew), but after he murders someone and almost sinks the ship, he merely gets his hands slapped and everything goes forward.
If you kill someone in a boat under the sea, what, it doesn’t count? The film’s disregard for what he did is odd. And it won’t be the last murder Fraser commits.
When the crew locates the Nazi gold, Fraser is out on the ocean floor and one of the crew falls down a pit to his death. Fraser seems genuinely upset about it for a while, sulking with his head down upon their return to the submarine. He even gets chummy with Tobin (Bobby Schofield), the young non-sailor on board the vessel, for some time, as if the experience on the ocean floor impacted him for the better. That is, until the plot calls for another on-board issue that halts the progression of the submarine’s work, and Fraser savagely beats a man to death with a wrench. This renders the crew too spartan to properly drive the sub, and requires them to surface, forfeiting all the gold. This act not only diminished any evolution for Fraser’s character, returning him to the wretched villain he started as, but also made little sense for a man whose largest concern had been getting a larger chunk of the gold share.
"Early on, we are told that submarines are like whores – the old ones treat you best. Unfortunately, the screenplay here proves as leaky as their ancient, Soviet-era vessel. The behaviour and motivations of the crew-members, especially that of the near-psychopathic Fraser (Ben Mendelsohn), are hard to fathom." - Geoffrey Macnab, The Independent
Arguably psychotic, perhaps Fraser’s waterworks during the middle of the film presumably were all an act. Perhaps his only objective all along was to off as many fellow crewmen as possible to maximize his share, and his final kill was Fraser’s own acknowledgement that the situation was hopeless. Perhaps even someone as unstable as Fraser saw the futility of their task by that stage, and opted to take his chances surfacing rather than die at sea.