Complex sentence: The idea for the "30 for 30" series began with ESPN.com columnist and Grantland.com founder Bill Simmons and ESPN's Connor Schell, who wanted feature filmmakers to recount aspects of sports history that had not been fully explored.
Split into simpler sentences: The idea for the "30 for 30" series began with ESPN.com columnist and Grantland.com founder Bill Simmons and ESPN's Connor Schell. They sought to detail aspects and perspectives of sports history that had not been fully explored.