Great Graphics+Revolutionary gameplay= HL2
Gameplay- Physics, Physics, Physic. The realistic and interactive environments create some really great gaming moments that will leave you with your jaw on the floor for five minutes. Foremost among these are the boat ride and the final level.
Story- Unfortunately, it is a bit weak, but hey get a freakin' imagination and beef it up. More details on the invasion, the plans of the Combine and the state of humanity could have been added.
Difficulty- Easy most of the time hard at times. Solution to puzzles are often surprising.
Overall- This game is a must-play for anyone, especially FPS'ers.