Best recognized for his role as Leon Black on “Curb Your Enthusiasm,” J.B. Smoove joined Fox’s ” ‘Til Death” two-thirds of the way through last season as new mainstay Kenny, a recently divorced free spirit with bad advice to burn. Smoove, a standup vet and former “SNL” scribe, is the exec producers’ not-so-secret weapon aimed at reviving a tired married-life storyline that lands so-so ratings.

The recipe for revival from creators Josh Goldsmith and Cathy Yuspa calls for husband and wife Eddie and Joy (Brad Garrett and Joely Fisher) plus footloose Kenny, occasionally on skates. The show’s younger couple (Eddie Kaye Thomas and Kat Foster) gets subtracted from upcoming season three.

Late-bloomer Smoove, who worked early MTV pilots before bigger breaks in “Everybody Hates Chris” and “Curb,” is a seasoned improviser. He sees the cast shift as a chance for more diverse humor.

“You don’t want to see your own household on TV,” Smoove says. “(With the different ensemble) we can cover more topics … even race relations. People are going to be surprised. (Eddie) needed Kenny at this point in his life.”