Quake 4 is the sequel to Quake 2 story wise..

Quake 4 is actually the sequel to Quake 2 story - wise. The game was developed in a collaboration with Raven Software and ID Software where ID supervised the development. The game is heavily focusing on the single player part. And that is the best part of this game.

The story continues where Quake 2 left off. You are again fighting off the alien race named Strogg where you have to secure the aliens home planet Stroggos. It is this story the game focuses on. There is a multiplayer option too but that didn't get so much attention because it is like a bad port of Quake 3. It is in my opinion much better to just play Quake 3 Arena if you would like to play online.

Seems like the game is playable on a regular MacBook too!, check the video below: