'This Is Us': John Legend to Guest Star in Season 4

John Legend at Royal Albert Hall in London in December 2019
Scott Garfitt/NBCUniversal/NBCU Photo Bank via Getty Images

The 'Voice' coach is lending his talents to the drama series. Meanwhile, Chrissy Teigen was hilariously unaware.

The Pearsons are about to welcome a legend.

John Legend, who is already part of the NBC family as a coach on The Voice, will guest star in the fourth season of This Is Us. Legend's surprise appearance was revealed in a promo that aired during the Golden Globes on Sunday.

While details weren't immediately available on how Legend fits into the storyline, the EGOT winner was briefly seen seated at a piano looking dapper in a tailored suit, presumably playing himself.

If Legend were to cameo as himself, he would not be the first to do so on This Is Us. Over the course of its run, This Is Us has has recruited Sylvester Stallone, Ron Howard and M. Night Shyamalan to play themselves.

Following the promo's debut, a fan tweeted at Legend's wife, Chrissy Teigen, about his upcoming appearance on the show. Teigen was hilariously unaware, thinking they were using one of his songs in a future episode.

"I had no idea until now and still don’t get it? his song or himself?" Teigen tweeted Sunday evening. 

Way to be kept in the dark, Chrissy!

This Is Us returns Tuesday, Jan. 14 at 9 p.m. ET/PT on NBC.

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