A pretty innovative game (although see also The Ship and a couple of others in the same ballpark) that has its flaws, but can be pretty fun once you get the hang of it all. Basically you play an actor that needs to kill the other actors in the movie so you can be the star.
Although there are a few game modes, the core is The Hunt - you have one opponent to kill, while someone else is tasked with killing you. So essentially you have a FPS version of Chompy Chomp Chomp and you rush about collecting weapons and items to help you, heading to where your target is on the minimap (or you get regular notifications when they move to a new area of the map), while trying to avoid traps and other people who might be out to kill you themselves.
The learning curve is pretty steep - you really need to know the maps intimately, including what each area is called, and what the quickest routes to get there from where you are is (there are usually dozens of routes as there are ladders, stairs, doors, corridors - pretty much every room/area has 4 or 5 ways out, and many have 10 or more. You also need to know where the weapons and traps are and how to use some of the more esoteric weapons like the rat bomb (and when to use it), and how to best use the bonus items which can be game changing when properly applied. Plus you need to know where all the traps are, and critically where they can be triggered from so that you know when it is safe to pass through. And then you need to track which weapons are currently good to use, as well as knowing the ins and outs of the different game modes, which will be switched every few minutes.
The weapons are not really balanced, but this is kind of as designed - this is mitigated somewhat by the scoring system - the good weapons usually get enough use they rarely ascend to a being a high scoring weapon after the first round, but in practise getting an easy kill for average score beats a strategy of trying to successfully use every awkward weapon in a cycle as they get to 5*. Another issue is the Blood Money round, which basically scores way to highly, such that most of the rest of the game often becomes a tie breaker between the people that did well in that one round.
Once you have the hang of it, and have some friends who also do, things finally click and you will probably start having a Bloody Good Time, but I can see plenty of people deciding that getting to that point isn't worth the payoff, as even then this game is quirky, flawed and not particular well balanced.