That day is not today.
Today there is only icy darkness and suffocation.
“A devastating disease has struck an alien planet,” explainsthe Steam page.

“The government has frozen the surface of the ocean in response.
You and your crew are trapped below the ice.”
Anyway, where was I?

Oh yeah - up to four submariners per sub.
You will “uncover snippets of information relating to a greater truth”.
Of importance: making sure you have enough room on your sub for cannisters of fuel.
you might’t fuel a submarine’s engines with sledgehammers.
There’s also the prospect of encounters with other submarines.
you could negotiate with them.
Also, your submarine can be upgraded with rooms for specialised tactics such as hacking and stealth.
It sounds like there’s plenty to chew on.
Try that on for size, Sea Of Thieves.
Darkwater is coming to Steam early access in 2025.
The current biggest mystery here is how they’ll support single player properly - bots?
I wouldn’t trust a bot at two thousand fathoms down.