It's Sweethearts Day in the Kingdom of Avalor. Marlena is handing out orchids to everyone in the spirit of the holiday. At Avalor Palce, Elena and Flo discover that Armando wants Marlena to be his sweetheart. Armando sings them a song he wrote for her only to find his singing sounds horrible. Armando wants to use magic to make himself sound better. Elena tells him he just needs to be himself. Flo however agrees with Armando's idea. Meanwhile, Luisa and Isabel have set up a Sweethearts Day lunch for Francisco but it seems he's forgotten about it.
Meanwhile, Flo and Armando have gone to Mateo's workshop. They whip up a potion to make his singing better. Unfortunately, all it does is make everyone but him sing nonstop. Mateo discovers the reversal potion but they need to get the final ingredient from Dona Paloma. Meanwhile, Isabel discovers that her grandfather is trying to make a cake for Luisa without success. Luisa doesn't mind and spends the day with Francisco.
Meanwhile, Mateo has whipped up the reversal potion. For it to work, Armando needs to sing from his heart. Armando does so and breaks the spell. Soon, he happens to see Marlena, who gets surprised and runs off. Everyone is confused and shocked, especially Armando. Back in the castle, Armando feels heartbroken because he thinks he was refused by Marlena. Elena gives a cup of tea to Armando to cheer him up. When he is about to drink it, however, he hears someone singing. When they go out, they see Marlena singing to Armando with her guitar. After she finishes singing, she asks Armando if he will be her sweetheart. Armando gets confused, saying that Marlena ran away from him earlier. Marlena says that she was only getting her guitar so that she could sing a song for him as well. She also explains she loves how Armando sang from his heart and how brave and sweet he is. Hearing this, Armando feels delighted and accepts to be Marlena's sweetheart. They hold each other's hands and go get sweetheart stew together.
- Aimee Carrero as Princess Elena
- Joe Nunez as Armando
- Gaby Moreno as Marlena
- Kether Donohue as Flo
- Jenna Ortega as Princess Isabel
- Emiliano Diez as Francisco
- Julia Vera as Luisa
- Joseph Haro as Mateo
- Constance Marie as Doña Paloma
- Carlos Alazraqui as Skylar
- Something in the Air
- Sweeter Days
- Sweetheart's Day
- All You Need and More
- You Gotta Sing
- The Perfect Girl/Guy for Me
- Moral: It's important to be yourself to impress others.
- This is a musical-themed episode, making this episode feature the most songs (a total of 7) out of all the episodes in the series, including specials.
- The plot is similar to the Vampirina episode "The Vamp-Opera", when a spell causes everyone to sing consistently.
- Mateo implies the Palace doesn't pay him enough.