In 1974, Snake (a.k.a. Big Boss) is no longer part of the US special forces and has his own merc team. While on a mission in South America, they encounter a strange hostile merc unit with far superior equipment than their latest tech.
Robin Atkin Downes,
When the nations of the world rely upon private military companies to fight their battles for them, renegade Liquid Ocelot emerges as the head of a potent coalition of mercenary powers. Solid Snake returns to save the world once again.