Andy Samuels, Amy and Tess' cousin, comes to visit. She asks Amy if the they want to something fun, but Amy insists on being alone. Later that day, Amy, Brenna, and Kelsey go to the pier, claiming that it's been too long since they've last swam to the cave. When the get there, the waterfall hits them and they become possessed.
The three mermaids wake up in different places and can't remember anything that recently happened. Brenna finds a fish and Kelsey finds shrimp in Amy's hair. Amy then remembers her aunt and Andy and runs upstairs, only finding her aunt. Amy and Brenna wonder about whether or not Brenna had another "hulk" experience, while Kelsey finds a grocery receipt that explains the shrimp. While they search the store for clues, Amy finds a resume for a carnival. When the go there, Brenna finds a certificate for a corn dog eating contest and wins an ticket for free ice cream. When Kelsey asks for some, Brenna accidently spills a little on her shoulder. She goes to wipe it off and discovers a red mark on her shoulder. When they're about to give up, they discover on a news cast that a random fire started in the middle of the night. They explore the site, where Brenna finds Andy's shoe ("I found a hobo's shoe."). After realizing that Kelsey's mark was a fish, they conclude that Andy is ether at the pet store or the zoo.
While they're checking out the pet store, Brenna sees a blond chick unconcious and covered in shrimp. They realize that the girl is Andy and they take her home. After waking up, Andy tells Amy what she thinks was a dream about them going to random places. When they were at the pet store, they whispered to the water and it moved and attacked her. Andy then goes to get something to eat, wondering why she smells like shrimp.
Andy is introduced in this episode played by McKenna.
.Andy reveals that Amy got stuck on the roof once.
Brenna reveals that she hates corndogs.
Amy says that her mom is allergic to shrimp.
The girls wake up in random places that involve their powers:
- Amy in a bathtub with seashells.
- Brenna in the sunlight with a tiki torch.
- Kelsey in a mini cooler filled with ice.