After an overly ambitious businessman transports an 80-foot python to the United States, the beast escapes and starts to leave behind a trail of human victims. An FBI agent and a snake specialist come up with a plot to combat the creature by pitting it against a bioengineered, 70-foot boa constrictor. It's two great snakes that snake great together!

Athos, Porthos, Aramis and D'Artagnan remember their youth and adventures, long battles and amorous adventures, they feel sorry for their Captain de Treville and do not lose sight of their eternal enemy - the Cardinal.