Season 2 is to premiere Feb. 4.
"Who Do You Think You Are?" is an adaptation of the British television documentary series in which celebrities learn about their family trees, NBC said in a synopsis.
"I've been a fan of the U.K. version of 'Who Do You Think You Are?' for a long time, so it's very rewarding that the U.S. version is back with more compelling stories this season that are illuminating, touching and aspirational," executive producer Lisa Kudrow said in a statement Thursday. "This is such a unique show for network television and we're all thrilled that the American audience has embraced it."