Upon reaching the suspension bridge leading to the Detention Camp, Gustava is killed by a missile fired by Metal Gear D and Dr. Madnar is recaptured by the enemy. The new Metal Gear's pilot is revealed to be none other than Snake's former mercenary buddy Gray Fox. Determined to finish his mission, Snake fights against Zanzibar Land's elite mercenary force and manages to reach Dr. Marv's cell.
Snake arrives too late, unfortunately, as he finds the corpse of Dr. Marv, who was unable to survive the repeated torture. Dr. Madnar is also there and explains he was unable to save him. Just before Snake could retrieve the OILIX formula left by Dr. Marv, Holly reveals via a radio message that Dr. Madnar was not captured after all, but voluntarily resumed his work on Metal Gear and was personally overseeing its development. After the truth comes out, Dr. Madnar attacks Snake, but fails in killing him.