The Death of Henry the hippo shocks everyone at Funjungle. The main character, Teddy, watches it all go down. The staff then try to get the doctor; as they do, they decide to do an autopsy on Henry. They would see Henry might have been killed since there were holes in his intestines. Teddy then goes back to his mom, who knows he went to the autopsy and doesn't want him doing it. The next day he sees Summer McCracken, the son of J.J. McCracken, the CEO of Funjungle. He tries to inform her that Henry was killed.
Summer actually wants to investigate who killed Henry, so they try to enter Henry's exhibit. Summer has a code for everything, so they start swimming around, and they find something that could have killed him: a jack. They then took a shower, and Teddy took the jack to the doctor, who told him he shouldn't be investigating. Summer told Teddy to meet up in the world of reptiles, but once he came, no one was there, and the black mamba was out of its container. Then Teddy got really scared it could be anywhere, so he ran out, After Teddy almost was killed by a snake, his mom said she didn't want him to roam around since the person might be after him, but once his mom left, he still went out to meet up with Summer behind the dumpster. Then they talk about the grand opening at Carnivore Canyon that they both agreed to go to, potentially looking for more clues, but then they suspect that someone in the mascot room knew who killed Henry, Charlie Conner, so they go into the mascot room.
They started talking to Charlie, and he talked about henry's past shenanigans, which included putting someone in his mouth and biting Charlie's leg. He also said Pete Thwacker might have been a part of it and hired Large Marge to kill Henry. After that, his mom was pretty mad he sneaked off, so she made him stay in his room and confiscated his phone, and then he thought about how dumb Pete and Marge are and thought they wouldn't do it. And then Buck came along and said Charlie is an ex-convict not to be trusted; then Teddy's mom came along, and Buck wanted to help, knowing about the cameras and whether they could see any suspects. After that, they attended the Carnivore Canyon grand opening. They were looking around, and then they found J.J. McCracken; they then talked about Teddy letting the Security figure it out and stepping back. Then, they saw a tiger in front of them that had escaped. It was about to get them, but then Teddy's dad came in to save them. The tiger went to the actual party down there, disturbing the peace and eating all the food, then he got forced back to his enclosure by keepers.
First, they decided to go to the administration room to learn about the metal groove in Hippo River but it had tons of security. But Henry's funeral was coming up, so they thought it would be empty when they got up there, and as expected, no one was there. But once they opened up blueprints, they were disgusted; it was all types of rides- river rapids, coasters, boats, etc. They were using these inside of animal enclosures when they could get seriously hurt, and that's when they realized what the metal groove was for: a ride in the enclosures when the animals can attack the boats or get seriously hurt by them. But that's when Buck Grassley and other security guards went in and arrested Teddy's mom and dad. They tried to fight it, but the guards were too powerful; that's when they spotted Teddy, and he sprinted out. And then he ran into the funeral. Buck tried telling people that he was bad and to get him; some people tried to get him, but he was too quick. He tried to climb up the crane, and the guard accidentally hit the crane operator, and Henry's coffin that the crane was holding dropped, and his insides were everywhere; it was gross. People tried to get it off, running to the showers and throwing up. That's when he had the chance to run; when he looked at Summer, she looked at him weird, and that's when he realized she turned him in. Buck made everyone think that Teddy's parents were a part of the ALF, so they got charged. And he ran to Doc, maybe thinking he got a few last clues. Turns out, Doc knew about everything, and that's when he said, "I think Martin del Gato killed Henry," and it made sense. he said he smuggled emeralds and put them in animals, Henry being the case here. The reason Doc helped was that Martin blackmailed him into doing that, saying he would turn his daughter in to the FBI, who was actually a part of the ALF. but they saw security was coming, so they got in docs truck and drove, they encountered rhinos, wart hogs and water buffalos but they got past them, making them all hit the securitys land rovers teddy had to get out the truck and hide, but when they saw him he ran, then he encounterd large marge and conner, but he got the code in time before they got him when he got near summer, he got tackled but he told J.J that martin del gato killed henry. But instead, Martin blamed Buck. Martin said the hippo accidentally ate the emeralds, and they waited for him to poop them out, but it took too long, so Buck used jacks to kill him instead. After the autopsy, they picked up the emeralds in the auditorium. It turns out Buck was the one who set up Henry with the black mamba and the tiger. Buck tried to escape, but Large Marge punched him unconscious, wrapping up the case.