The Mark is an action first-person shooter with a plot about fanatical terrorists planning the ultimate strike. From the son of a Russian millionaire, they have obtained a nuclear warhead, and from Iraq, a carrier rocket. Their target: London, England. Two specialists have been called to stop the madness. For Steve Fletcher, a U.S. Marines elite officer, it is also a personal vendetta – the terrorists have kidnapped his sister. For mercenary Austin Hawke, it is the assignment of his life. Their respective routes through the game are slightly different.
The game features 2 single-player campaigns, each with 18 levels in 6 different chapters, with 15 different weapons. In the single-player mode players choose either to play as Fletcher or Hawke, or both simultaneously in the cooperative multiplayer mode. There are also other multiplayer modes, such as Death Match or Map Control and players can create their own multiplayer maps with the included level editor. Screen blur is incorporated for realistic shot effects. Watch out for potential suicide bombings and gunshot ricochets.