My big fat zombie goldfish

"When Tom's big brother decides to become an Evil Scientist, his first experiment involves dunking Frankie the goldfish into toxic green gunk. Tom knows that there is only one thing to do: Zap the fish with a battery and bring him back to life! But there's something weird about the new Frankie. He's now a Big Fat Zombie Goldfish with hypnotic powers...and he's out for revenge!" -- Back cover.

Tom and Pradeep go on a camping trip and question Tom's older brother's involvement when paranormal pets go missing. Tom must protect his big fat zombie goldfish Frankie before he ends up among the missing.

Frankie was a completely normal pet goldfish until Tom's evil-scientist big brother Mark tried to murder him with toxic gunge. Luckily Tom and his best friend Pradeep shocked Frankie back to life with a battery, and he's been their zombie-fishy friend ever since. On a trip to the aquarium, something fishy starts going on. Something that almost certainly involves evil older brothers, a vampire kitten, a psychic octopus and a plot to take over the world....