I wanted to like this game more than what I managed to. It's a terrible tragedy! The game is novel in that it attempts to weave documentary like presentation through that of the eyes of a fictional protagonist, however it has numerous heavy flaws of all stripes that sink itself under it's own weight:

-From a technical standpoint the game is a bit laggy and choppy (Unoptizimed)
-from a design standpoint you have a ton of annoying collectibles that serve no place in the game and only take one out of the experience
-To top it all off you are navigating cramped confines of a submarine, which are quite disorienting and the HUD seems to hinder as much as help.
-Finally, much of the progression is linear fetch quest tpe fare in a stalwart and tedious type maze like environment that is generally, slow to move through and not much fun to go back and forth between.
-From a meta standpoint it does very little to really elucidate the background nature of events. (which seems to be the underlying intent?)

In the end you are left with a janky thing that feels like half a game at best, despite what is an interesting premise for a genre that new ideas are welcome. This thing is tedium to play through, as most of it is an outright slog, and it has a hefty price tag. I could not recommend this game unless you specifically have a tailored or heavy interest in naval history and/or vessels. If you are curious, by all means just watch a "let's play" of it.

To the game's credit it did hit two nice bits:

-a huge sub full of many different facilities (a swimming pool!) and all sorts of weird mysterious russian stuff to ogle over.
-a rather cool intro with interactive conversation with a cabbie reminiscent of the Skyrim cart ride. -It also doesn't bog down on obtuse puzzles, though there are a few annoying minigames one must complete (Something I really appreciate of adventure games to shy away from)

In conclusion this game barely avoids abysmal ranking. Which is a shame cause it had a noble intent. I like russian games, and I like janky stuff fine, but this thing is a disaster!