Batcat and Al the Ghost are great roommates-Batcat even shares their eye scream occasionally-but sometimes Batcat still craves solo them time. When Batcat visits the Mermaid Lagoon for a relaxing day of reading all by themself, they discover the local mermaids in hysterics all over the beach-so much for quiet day on the sand! It appears that something has drained the color from all the mermaid's tails, and they won't leave Batcat alone until the half-bat, half-cat reluctantly agrees to help find out what happened. With a bag of the mermaid's famous fish tacos on the line, Batcat will meet more zany inhabitants of Spooky Island and overcome their greatest anxiety in order to solve this colorful mystery!