Deep in the Congo Rainforest, a genetics research facility has gone dark. A partial distress call, sent moments before the blackout, indicates that something sinister has occurred. With research worth billions and secrets worth killing for, the notorious Lexington Corporation recruits Ziler and his team of mercenaries to investigate.

He was told it would be a quick assignment. Drop into the Congo Rainforest, find the secret genetics facility, download all research data from the main computer, and bug out. What they find is the deadly result of tampering with nature.

The simple assignment becomes a fight for survival as giant mosquitos emerge from the canopy. Capable of draining a human body of blood within seconds, they quickly prove themselves to be the deadliest threat Ziler's team has ever encountered. Driven by instinct, they are fearless creatures whose sole purpose is to feed relentlessly.

Now, Ziler and his mercenaries are next on the menu. Eager to keep their blood in their veins, they fight to kill the bugs and prevent them from multiplying.