Brink is a multiplayer shooter set in a future in which almost the whole earth is flooded by water. The Ark is one of the last inhabitable places left, but there is a conflict between the security guards and the resistance. Now they are in open conflict and try to get the upper hand. The game features two single-player campaigns, but those are practically the same as the multiplayer, just with bots and cutscenes.
Every map has several areas, all with their own goals. Of course the goals of security and resistance are opposed, so for example in one area the security first has to blast the gate to the rebel hideout and the resistance has to foil their plan while pursuing their own goals. All those goals need the use of one of the four classes: the soldier is responsible for brute force, medics heal their buddies, engineers can use gadgets and agents hack computers. Overall there are four basic mission types (escorting, destroying, defending and using a device) along with class specific goals. Brink utilizes an automatic mission system, meaning if a player soldier starts the mission "planting a bomb", all other players receive the mission to defend him. Performing those missions rewards experience points which can be used to upgrade the player characters and unlock new abilities for them.
Overall the focus in this game lies on teamwork, and there are many ways for the classes to help each other out. If there is the need for a specific class, the player can always change his class from an in-game terminal. When creating a new character, the game offers many options for individualizing; but this has only optical effects. The one exception is the body measures; a big guy can use big guns while a light character is faster. The latter also has access to the so-called "SMART" system, which allows them to climb over obstacles or slide over the ground when holding a button.