Contestants are given a two-minute head start as they face off against the Defenders, a group of elite athletes whose goal is to defend the million-dollar prize, in the most challenging one-mile course ever designed, in the streets of downtown Los Angeles.

A former college quarterback attempts to outrun the youngest Spartan Race winner in history.

A yoga instructor faces a defender who has competed in 54 triathlons, and Trevor Bell, nicknamed "Spiderman," attempts to outrun "The Sherriff," pound for pound, the fastest man on the planet.

A father of quadruplets faces "The Captain," a green beret who holds the record for most podium finishes in the Spartan Race World Championships and a former ballerina goes toe to toe with an obstacle course racing professional.

A former women's college basketball player gets a fast break against 'The Harvard Hammer,' a medical student who holds an All American title. Also, a self-taught gymnast goes for the gold against 'The Beast from the East,' one of Russia's leading stuntmen.