Kim Gu-ra, Park Myeong-soo, Ji Sang-ryeol, and Lee Sung-jae have something in common: They all were born in 1970, which means they are now 50, reaching half of their lives in the era of longevity. The show follows four middle-aged men who still want to do more in their lives, checking up on their half-century lives. They will get a question every week about life and do their best to find answers.