Star and Marco go to another dimension to find a sandwich. A monster tries to eat them, and Marco returns to Earth with Star while only getting half the sandwich. Star is furious that Marco didn't let her get the whole sandwich, while Marco says a sandwich is not worth dying for. After their fight, Star goes to talk to Marco again, but he is nowhere in sight. Star eventually finds the Fly Monster, who tells her that if she wants to see Marco alive again, she must take her wand to Ludo's castle alone.
Meanwhile Ludo attempts to get Buff Frog on his side again, carrying a sack which, when Star arrives, she thinks Marco is inside, but instead turns out to be tadpoles for Buff Frog to adopt (hoping that their friendship will motivate Buff Frog to take Ludo's castle back from Toffee). Ludo tells Star that Toffee took over his castle, and eventually the three join forces to defeat him. Though Buff Frog appears reformed due to the tadpoles, Ludo still intends to get Star's wand.
They enter Ludo's castle where Toffee has Marco imprisoned in a near-impenetrable glass box. Star blasts Toffee's left arm off and fights Ludo's army, then enters a more powerful state and destroys the glass box, however, the box regenerates before Marco can escape. Toffee regenerates his lost arm and threatens to crush Marco with the box. Star is forced to give Toffee her wand. Ludo tries to take it but is eaten by Big Chicken. Toffee reveals he does not want Star to give him the wand; he wants her to destroy it. Star reluctantly uses the Whispering Spell to destroy her wand. The unicorn powering the wand briefly appears as a spirit in death.
Toffee stops the box from crushing Marco, and Star gets into the box with Marco and tells Buff Frog to run. As a result of the Whispering Spell, the wand explodes, obliterating Ludo's castle, and presumably Toffee as well. Star and Marco are shielded from the blast by the box, while Ludo appears from an egg that Big Chicken laid before he and the other monsters ran trying to escape the explosion. Ludo is furious over the destruction of the wand and his castle, and Star banishes him to another dimension with the Dimensional Scissors.
A new unicorn repairs the destroyed wand, and then Mr. and Mrs. Diaz show up with the army of Mewni, who contacted Star's parents with the magic mirror. Queen Butterfly says that although she's always angry at Star, she is still glad that she is safe, and permits her to run after Mr. and Mrs. Diaz as they ride the horses. The king and queen contact Glossaryck, who says that the wand can be fully repaired if all its pieces remain. Half of the star faceplate of the wand is still in the monsters' realm.
- Eden Sher as Star Butterfly
- Adam McArthur as Marco Diaz
- Alan Tudyk as Ludo/River Butterfly
- Grey DeLisle as Moon Butterfly
- Artt Butler as Mr. Diaz
- Nia Vardalos as Mrs. Diaz
- Fred Tatasciore as Buff Frog
- Michael C. Hall as Toffee
- Jeffrey Tambor as Glossaryck
- In this episode, it is revealed that King Butterfly's first name is "River" from Queen Butterfly.
- It is also revealed that Mr. Diaz's first name is "Rafael" from Mrs. Diaz.
- This is the second half hour-long episode in the series, following "St. Olga's Reform School for Wayward Princesses".
- October 15, 2015 (United Kingdom and Ireland)
- November 20, 2015 (Poland)
- November 20, 2015 (Turkey)
- December 6, 2015 (Spain)
- January 28, 2016 (Israel)
- June 13, 2016 (Latin America)
- June 24, 2016 (Southeast Asia)
- July 16, 2016 (Japan)
Promotional and Concept