Octo, PI and The Mysterious Voice by Sarah McDavis

When a spooky voice shuts down comedy night, Octo P.I. sets out to prove it isn't a ghost. Luckily, she likes facts that stick and that makes her the #1 case closer at the ZAR&R. While following the clues, she tries to help a pirate with their lost treasure, to keep an eye on the Ghost Hunters's show host, and to solve the case before animals stampede!

OCTO, P.I. AND THE MYSTERIOUS VOICE is the second in this mystery chapter book series for 7 to 10 year olds where Inspector Flytrap meets Finding Dory and Zootopia.