“Nashville” is welcoming its biggest guest star yet: Sir Elton John. The “Tiny Dancer” singer is going to join the cast for Season 4, episode 20, and he’ll see plenty of behind-the-scenes drama during his stint on the ABC series.

“After nearly two decades, Rayna and Deacon face the facts of their storied and often tempestuous relationship,” the synopsis teases. In the previous episode, Deacon (Charles Esten) moved out and appeared frustrated with his life. The guitarist even bought a bottle of alcohol, but a phone call from Rayna (Connie Britton) stopped him from taking a sip. However, that might not save their relationship.

In the promotional video for episode 20, titled “It’s Sure Gonna Hurt,” Deacon seems to be leaving Rayna for good. “I’m done being the screwup in your life,” Deacon says.

Watch the trailer for “Nashville” Season 4, episode 20 below:

Meanwhile, the Exes will be separated this week. Scarlett (Clare Bowen) will be shooting her commercial while Gunnar (Sam Palladio) will get to make his dreams come true. “Scarlett makes a startling self-discovery in between tour dates while Gunnar performs with one of his idols, rock-music legend Sir Elton John,” the synopsis reveals. It looks like Autumn (Alicia Witt) might be the one to help Gunnar get onstage with Elton.

Nashville 420 synopsis Sir Elton John (left), Autumn (Alicia Witt) and Gunnar (Sam Palladio) meet backstage in “Nashville” Season 4, episode 20. Photo: ABC

“Elsewhere, Juliette struggles to make a connection, and Layla [Aubrey Peeples] launches her album at The Bluebird,” the summary teases. Juliette (Hayden Panettiere) reconnected with Noah (Derek Hough) in the previous episode. While he was eager for a relationship, she didn’t appear too confident about it. Is he a little more interested than the country star is?

Finally, Luke (Will Chase) will work on his career, which has not been doing well since he began supporting Will (Chris Carmack). “Luke stops by ‘The View’ to trumpet a worthy cause, before a family emergency pulls his focus.” The hosts of the TV talk show — Joy Behar, Paula Faris, Whoopi Goldberg and Raven-Symoné — all will appear in this episode. It isn’t clear what kind of emergency will pull Luke away from the talk show, but it may have something to do with Colt (Keean Johnson). He hasn’t been heard from since he enlisted in the Army, and Colt is scheduled to be seen in episode 20.

“Nashville” Season 4, episode 20 airs on ABC Wednesday, May 18, at 10 p.m. EDT.

Nashville Noah West Noah (Derek Hough) is introduced to Juliette’s (Hayden Panettiere) daughter in “Nashville” Season 4, episode 20. Photo: ABC

Nashville Derek Hough Noah (Derek Hough) spends time with his new girlfriend in “Nashville” Season 4, episode 20. Photo: ABC

Nashville Elton John Sir Elton John and Gunnar (Sam Palladio) perform together in “Nashville” Season 4, episode 20. Photo: ABC Nashville Avery Layla Layla (Aubrey Peeples) looks irritated as Avery (Jonathan Jackson) attempts to comfort her in “Nashville” Season 4, episode 20. Photo: ABC