At the start of the game, Raiden is working for the PMCs to raise money for his family, performing multiple tasks such as the training of armies and VIP protection in an unknown African country that is recovering from a previous civil war.

Solid Snake is a legendary infiltrator and saboteur. During the mission, Snake receives support and advice via codec radio. Colonel Roy Campbell, Solid Snake’s former commanding officer, supports Snake with advice and tactics.

The world economy relies on continuous war, fought by PMCs, which outnumber government military forces. PMC soldiers are outfitted with nanomachines to enhance their abilities and control the stress on the battlefield. The control network created through these nanomachines is called Sons of the Patriots (SOP), and Liquid Ocelot is preparing to hijack the system. Snake accepts a request from Roy Campbell to terminate Liquid, with Otacon and Sunny providing mission support from the Nomad aircraft.

A secret agent from an elite special forces unit who is sent on solo sneaking missions through enemy installations, vast jungles, and sometimes even the thick of battle. Alone and surrounded by the enemy, even a special forces agent will find it tough to come out alive. But that is the secret behind the series’ popularity – the cerebral challenge of figuring out how to avoid combat, and the thrill of sneaking through enemy territory undetected.

Set in 1975, sometime after the events of Peace Walker, players control returning protagonist Big Boss/Snake as he works with Militaires Sans Frontières to infiltrate an American black site on Cuban soil called Camp Omega.

In the aftermath of the events of Ground Zeroes and the destruction of Militaires Sans Frontières, Big Boss falls into a coma.