Adele is used to surprising fans at her concerts, but this time she was the one who was left shocked. The "Easy on Me" singer filmed a UK concert special called "An Audience With Adele," similar to CBS's "Adele: One Night Only," that aired Sunday night across the pond.
The channel's Twitter account tweeted out a clip from the event, held at the London Palladium, where actor Emma Thompson asked the superstar vocalist about her childhood mentor.
Thompson wondered if Adele had someone who supported, inspired, or protected her "from all the trials and tribulations of life" when she was younger.
"Yeah, I had a teacher at Chestnut Grove who taught me English," the 33-year-old singer responded. "That was Miss McDonald."
"Did you ever keep in touch?" Thompson asked, seemingly aware of what was going to happen next.
Adele said she hadn't seen the teacher since she was 12 before she started praising her.
"She was so bloody cool," the singer recalled. "So engaging. She really made us care and we knew that she cared about us."
"Yeah, cause it's odd, actually, funny enough…" Thompson said, trailing off.
Finally catching on, Adele looked to the audience and asked "Is she here? Is Miss McDonald here?"
Her former English teacher emerged from the crowd as the room erupted with cheers and applause. As McDonald approached, Adele broke down in tears and said, "Hi! You look amazing darling!"
The two hugged and McDonald replied, "Oh my God, I'm so proud of you."
When Adele said she did not expect the reunion, McDonald assured her, "That's OK. It was supposed to be a surprise," as the singer laughed.
McDonald shared that she no longer teaches and now focuses on raising her children. "Thank you for remembering me," McDonald sweetly told her former student.
"No, you really did change my life," Adele said before hilariously turning to the audience and saying, "Mum, can you believe it?"
McDonald then pointed out her two children in the crowd.
Before McDonald returned to her seat, the "My Little Love" singer asked if she could have her phone number. She added, "I've still got my books you know! I've got all my books from when you were my teacher."
The singer then briefly departed the stage to fix her makeup after all the crying. Shots of the crowd revealed celebrities like Emma Watson, Dua Lipa and Idris Elba were in attendance to see the tearful reunion.
After the special aired, the singer tweeted about the meaningful evening and included a shoutout to her former mentor.
She wrote, "Home Sweet Home. I've always dreamt of doing 'An Audience With…' There was so much love in the room for eachother, it felt like such a gig! Everyone was raucous and bang up for it! And my teacher Ms McDonald was there, it was just heaven," along with a heart emoji.
The heartfelt interaction followed Adele creating another emotional moment during CBS's "Adele: One Night Only" where a fan asked his girlfriend to marry him.
Adele asked the audience to be silent as Quentin proposed to his girlfriend Ashley in front of the musician and the entire crowd at the Griffith Observatory in Los Angeles.
After Ashley put the ring on her finger, Adele joked, "Thank God she said yes because I didn't know who I was going to sing this song to next, you or him!" before crooning along to the ballad "Make You Feel My Love."