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John Legend Will Guest Star On 'This Is Us,' So Start Emotionally Preparing

This Is Us Season 4 returns in January, as the characters once more head out on a path where the audience already knows the destination. As with the first half of the season, the questions hinge on what steps these characters take to get there. Why aren't Kevin and Randall speaking? How smoothly does the road to divorce run for Toby and Kate? And what does John Legend have to do with this? Wait, what? That's right, TIU fans, John Legend will guest star in This Is Us, and from the looks of the clip, he'll be singing to tug our heartstrings.

Fans had seen little of the This Is Us family since the pre-Thanksgiving mid-season break. A short promo for Season 4, Episode 10, "Lights and Shadow," suggested Toby and Kate's marriage will hit a fork in the road, but other than that, there was nothing major to note. So when a short teaser aired during the Golden Globes on Sunday, Jan. 5, it was like water in the desert.

Not that there was much to see. Once again, the only clip with dialogue was the same Kate and Toby confrontation from November's promo, with Kate asking, "I feel you pulling away. Am I crazy?" But a few new images were included, the most important of which included a guest spot for singer/songwriter John Legend, seated at a piano.

The surprise wasn't just for fans. Apparently, Legend's wife, Chrissy Teigen, was also in the dark. When fans started tweeting at her, she wasn't even sure if they meant Legend or just that one of his songs was featured in the promo.

With that kind of secrecy, it's not surprising no one has any details about his appearance at this time. Entertainment Weekly confirmed Legend will be part of the Season 4 in a guest role, but that's it.

Of course, the lack of facts means the speculation is running wild, with people guessing everything from a cameo as himself to Legend playing one of Toby's Crossfit friends. But without any confirmation one way or the other, fans will simply have to wait and see.

This Is Us returns with Season 4, Episode 10, "Lights and Shadow." According to the synopsis: "Kevin is still on the search for romance. Meanwhile, Kate meets Toby's Crossfit friends, and Randall travels to Los Angeles to be with Rebecca."

This Is Us returns to NBC starting on Tuesday, Jan. 14, 2020, airing at 9 p.m. ET.