From the back of the book: Welcome to the ultimate d20 system superhero roleplaying game. Silver Age Sentinels pushes the boundaries of the d20 system with exciting and innovative new rules.
Every age has its Heroes - men and women who refuse to believe that humanity has a limit for kindness and compassion. These heroes understand the power that an individual holds to change the direction of society. Through their actions, they inspire others to reach beyond their own perceived limitations and strive for greatness.
Believe. It will come true.