After thwarting a mid-air terrorist attack, veteran CIA operative John Clark is recruited to lead Rainbow Six, an elite international counterterrorism team granted preemptive strike capability. Clark assembles a multilingual unit of specialists and pursues ex-KGB agent Dmitriy Popov across Europe, uncovering a shadowy conspiracy targeting pharmaceutical companies. The trail leads to billionaire eco-fascist David Brightling, whose genetic research lab has engineered a lethal aging virus designed to cull humanity and "give Mother Nature a fighting chance." When Brightling's security plots to distribute the virus via cash at the Kentucky Derby, Clark and his team must infiltrate the event and stop the payout before 170,000 spectators become vectors for global annihilation—while Clark's kidnapped wife Sandy fights to escape Brightling's sealed compound.
