This is an absolute masterpiece when it comes to the FPS genre. If there was a game that I wish I could forget all memory of it just to experience for the first time again, it would be this game. Amazing narrative and gameplay rolled into one. I am very thankful that Valve made this free for a short while for people who hadn't played it yet to experience it. I myself played it many years ago, but you owe it to yourself to play this game if you haven't.