A really fun game to play, even today!
Firstly, I am still impressed with this game. The graphics for this game were amazing for its time. Even today, I can still say they are decent, especially considering it came out in 1996(Half-life came out in 1998 and Halo: Combat Evolved in 2001)! But alas how graphical standards change so much in only a few years time...
The gameplay is what I think is hit or miss for a lot of people. When I was a kid, I spent a lot of the time at local arcades right before most of them promptly met their demise, and some of my first video game memories come from playing rail shooters such as Deadly Tide. Basically, in this game you can control to an extent where you are looking when you play, however you have no control over your movement. This makes the game VERY linear in its progression, and frustrates many who wish do it their own way, but I look at it as simply another way to play a game, and it definitely forces you to aim well and memorize enemy placement at the harder difficulties.
The story... Well its not all that important to be honest, its 2440 or something and humanity is invaded by aliens that are technologically superior, but reside to living underwater, but still manage to cause earthlings much chaos. You take the role of an undersea fighter pilot who must try and put an end to this madness. Its all very flashy and very fast paced, and its pretty much all the excuse you need to shoot some underwater hide.
All in all: Back in the day, Microsoft Game Studios had some of the best games I had ever played (Age of Empires Series, Flight Simulator, Hellbender, etc). I believe this is one of those overlooked gems that either many gamers of that time don't remember, don't care, or weren't around for it. But I think it deserves a second look.