The Showdown on Boogeyman's Ship was a skirmish on Boogey Man's Ship, caused by Grim and company wanting to escape to beat Boogey's crew in finding the Horror's Hand.
Jury[]
At Billy's house, the Underworld Police take Grim away for the crime of abusing his powers. The jury is split up in pairs and each pair sits atop a giant pillar. To everybody’s surprise, Boogeyman is the prosecutor and is suing Grim for abusing his powers. Boogey mentions a lot of people stole Grim's scythe, including a turkey-salad sandwich! Grim is found guilty and the Boogeyman agrees to take him and the kids to exile while Numbuh Three from the Kids Next Door temporarily becomes the new Reaper, on a six week trial. They had someone else for the next six-week trial.
Billy and Mandy Escape[]
Grim says to Boogey Man to let the children go. Boogey Man replies "I don't think so". Grim happily said, "Fine. Take the kids, let ME go!". Boogey Man however said that he'll take each one of them, and took a picture of Grim to not forget him. Boogey's going to throw Irwin, Mandy, Billy, and Grim into the Lava Shark Pits so that they can be eaten by Lava Sharks. Before that happened, Boogey Man replied that he's going to kidnap Horror's Hand, & use it to be the most scariest creature to destroy the Earth's outer crust world and eliminate all children while they are sleeping in their nightmares when Boogey Man becomes the most scariest thing ever born.
Billy however starts "Scary-O", a song that is really awesome but Billy only used the song to make the bad guys get carried away singing. Mandy, Irwin, Billy, and Grim escape on the Death-Boat into the Lava.
The Crew Realize that the "Goody-Goodies" Escape[]
Creeper realizes that there is a deathboat missing, which means, the good-team is already on the river. Boogey is assured since the Gatekeeper's Magic Eye will get a grip on the four. After the four escape the cyclops from being stew, Billy ate the eyeball, and the cyclops are left to argue and yell "Shut up!" at each other and complain about dinner while the other team still escape.
Billybot and Mandroid, who have now just wasted their time with Billy's Dad at Billy's house, come back to the Boogey Ship, and float in a cake that has pink cream filling that reads Happy Birthday Billy and Mandy. Billy stuffs cake inside Grim and Mandy's mouth while Billy and Irwin are already busy trying to eat the cake. They each fall asleep under the potion of the cake by Billybot and Mandroid. Soon, the four are in a dream shared together in virtual reality. Soon, Boogey kidnaps Mandy and takes Irwin, Grim, and Billy sending into a fall to completely-redecorated United States, and Billy wakes up himself and the others when he pees. (Billy gets upset that there's pee in his pants)
Soon, Irwin gets ANGRY at Boogey and Creeper, into the power of love and acts like Tarzan!