The 21 season of The Ultimate Fighter was broadcast on ESPN from mercredi 22 avril 2015 to dimanche 12 juillet 2015. It consists of 15 episodes, the first one is called "Rumble In South Florida" and the last one "The Ultimate Fighter: American Top Team vs. Blackzilians Finale".
Sixteen aspiring mixed martial artists live together, train together and compete against each other to become the Ultimate Fighter. They receive coaching from UFC champions and contenders in a variety of martial arts including wrestling, boxing, judo, Jiu-Jitsu, karate and kickboxing. The winner receives a six-figure contract from the UFC.