The player plays as Chell, a woman who is a silent protagonist, and has pretty much no back story. The game is focused on using the Portal gun to get from point A, to point B, solving puzzles with weighted crates, gels that can make a surface bouncy, or make the character move very fast, and a lot of momentum. The voice acting is superb, by British comedian Steve Merchant (cowriter of The Office, Extras, and The Ricky Gervais Show), who is hilarious in this. It does have some voilent moments, though, the player character can be shot by turrets, fall in water, and be smashed, but nothing is shown. There are some creepy parts, such as finding writings on walls, and the robots talk about killing you often, and there is a pretty creepy, yet hard to find Easter Egg, but it's not a big issue, I wouldn't worry about anyone just stumbling in on it, you have to know what you're doing.