The announcement was made by Paul Telegdy, the network's president of alternative and late-night programming.
"When people see Ryan Seacrest, whether at the Emmys, the Oscars or New Year's Eve, he is at the epicenter of national events," Telegdy said in a statement. "He is a broadcaster, in all the traditional sense, but also in the most contemporary -- he is an accomplished host of live TV and a master of social media and pop culture. This makes him perfect for 'The Million Second Quiz.'"
"I'm so excited to be hosting this new live game show on NBC, as it's really a fun and different format that I believe will generate lots of fans across different platforms," Seacrest said. "I'm looking forward to working with the other producers and everyone at NBC to make the show a success."
The show is to premiere Sept. 9. It features "contestants playing head-to-head trivia bouts inside a massive outdoor hourglass-shaped structure in midtown Manhattan and competing non-stop for a million seconds -- 11 days, 13 hours, 46 minutes and 40 seconds," a synopsis said.
The series will air Monday through Saturday its first week from 8-9 p.m., then resume the following Monday and air in the same time slot through Sept. 19.