Richard (James Pickens Jr.) and Catherine (Debbie Allen) will have a feud that gets some of the doctors in Grey Sloan involved. Meanwhile, Maggie (Kelly McCreary) learns about Meredith (Ellen Pompeo) and Nathan's (Martin Henderson) secret.

On the next episode of "Grey's Anatomy" season 13, titled "Don't Stop Me," Richard and Catherine will be having a big fight that gets some of the doctors involved.

"Bailey (Chandra Wilson) and April (Sarah Drew) work to fix things between Richard and Catherine. Meanwhile, Eliza (Marika Dominczyk) continues to pursue Arizona (Jessica Capshaw), and one of Alex's (Justin Chambers) previous patients returns to Grey Sloan," the episode listing on The Futon Critic reads.

Meanwhile, Maggie accidentally finds out about the ongoing affair between Meredith and Nathan.

As seen from the episode 21 promo, Meredith and Nathan talk in a press conference about their recent experience from the plane where they saved a man's life by operating on him while their flight was going through turbulence.

Nathan tells the media that Meredith is the hero while they share an intimate look. In addition to that, Nathan also caresses Meredith's shoulder, which catches Maggie's eye. By then, Maggie will have already figured it out, and Meredith will have no choice but to come clean to her half-sister.

Season 13 of "Grey's Anatomy" is coming to an end soon, and showrunner Shonda Rhimes shared with Entertainment Weekly at the 100th episode celebration of "Scandal" that the finale will be "on fire," and that it's "a pretty exciting episode."

Allen, who directed the finale episode, also teased that, "it's going to be hot for real; it's on fire." However, it's not going to be the good kind of fire as Allen added that viewers should be worried about the upcoming season finale.

"Grey's Anatomy" season 13 airs every Thursday night at 8 p.m. EDT on ABC.