When Polly's special mermaid doll goes missing, she is convinced Pierce took it, and follows him into an escape room to prove it.
This episode includes examples of:
- Amateur Filmmaking Plot: Polly, Lila, and Shani are trying to make a movie about mermaids, but they keep getting interrupted by Pierce. Soon, their production is stopped altogether when Polly’s mermaid doll goes missing and Pierce becomes their #1 suspect.
- Answer Cut: At the end of the episode, Lila asks who actually took Polly’s doll if it wasn’t Pierce and Shani answers that they’ll never know. The scene then cuts to Paxton chewing on the doll and getting drool all over her.
- Bear Hug: Polly gives Pierce a big hug at the end of the episode and apologizes for accusing him of being a thief.
- Clam Trap: Polly and Lila get trapped in a clam shell when it snaps closed after they climb inside to retrieve a pearl - the key to the escape room door.
- Double Meaning: When he and Pierce read a clue that references a “siren song”, Austin mistakes it for meaning an emergency siren.Austin: Siren song? Ooh, is that like "Wee woo! Wee woo! Wee woo!"
- Explain, Explain... Oh, Crap!: After going through a long list of all the mean things he’s done to Polly, Pierce realizes she may have good reason for suspecting him of stealing from her.Pierce: Wow…I’m kind of a bad brother.
- Hey, You!: Austin only refers to Polly as “Pierce’s sister”.
- Hollywood Tone-Deaf: Pierce tries to sing the Mermaid’s Melody siren song in order to advance through the escape room, but his voice cracks horribly and the notes are all over the place.
- Improbable Aiming Skills: Lila is able to kick the mermaid’s pearl right into Pierce’s hand by sending it ricocheting off of several items around the room.
- Jackhammered Conversation: Pierce seems like he’s about to reveal whether or not he stole Polly’s mermaid queen doll, but then he turns up the radio and it’s too loud for Polly (and the audience) to hear anything else that’s said.
- Little Stowaway: While trying to get something out of Pierce’s backpack, Lila and Shani get stuck inside when Pierce picks it up and leaves. Polly soon joins them and all three have to stay hidden until her brother and his friend reach their destination.
- Losing a Shoe in the Struggle: In order to escape the clam shell she and Lila were stuck in while in tiny form, Polly uses her locket to grow her shoe to normal size and prop the two halves of the clam open. Unfortunately, though they’re able to escape, the clam snaps back closed and takes her shoe with it.
- Lost Food Grievance: Polly gets mad at Pierce for drinking her vanilla smoothies, leaving only spinach and kale smoothies for her and her friends to drink instead.
- Message in a Bottle: The first clue in the escape room is found in one of these.
- Mystery Episode: Polly and her friends try to solve the mystery of who took her mermaid doll and why.
- Red Herring: The audience is led to believe that Polly is right about Pierce taking her mermaid doll. However, it turns out that she was suspecting the wrong brother.
- Room Escape Game: It turns out Pierce was spying on Polly’s mermaid movie in order to train for beating the high score in a Mermaid’s Melody-themed escape room.
- Sibling Rivalry: Polly and Pierce both realize in this episode that they haven’t been treating each other the best and that they’re better when they work together.
- Talk Like a Pirate: Pierce does this upon entering the Mermaid’s Melody escape room.
- "X" Marks the Spot: The big clue that took a complex decoder to solve was simply “X marks the spot”. After learning this, the boys instantly find an “X” marked out in the sand with seashells.
