After Fritz-Carlos and Louis trick Fencer into going to the pool, the Cat leaves and tries to join the Cat Pack. unknown to Fencer, however, The Cat Pack intend to use Him for Their own ends.
The Story starts with Fencer chasing the Rat Brothers in the living room, and when the rats pull the window shade revealing a picture of a scary-looking dog, startling the Cat. Then, when Chucky and Baby let go of the window shade, Sammy, who was still holding on, was zipped inside, and waved a white flag, declaring that Fencer won out against the Rat. As Fencer announces His achievement to the Dogs, they unsuccessfully try to convince Him to come to the pool. Soon, Louis and Fritz-Carlos make a plan to trick Fencer into climbing a tree branch, which Louis uses to catapult Fencer into the pool. Fencer, furious from being tricked, leaves to join the Cat Pack, making Foofur berate Fritz-Carlos and Louis.
At the Cat Pack's hideout, Fencer tells the members that He's looking to become a member, but the Hench-cats toss Him out, but into the arms of Vinnie, who was hoping to see Him, surprising the Hench-Cats and Fencer. Vinnie then tells Fencer to pass a few tests to be in the Cat Pack. but Vinnie winks to His Hench-Cats saying that He has a plan. Back at the mansion, The dogs start to miss Fencer, as They see Sammy and Baby chased by Chucky (with a face of Fencer on a flag attached to His tail.) but The Rats say that They miss being chased by Fencer, making Foofur and the others check up on Fencer. At a street, Vinnie assigns Fencer to complete two tasks, One, get a truck's keys and Two, lock up the guard dog at the Willowby Aquarium. The Hench-Cats spot a fish market truck, and Fencer goes inside and grabs the keys, but is spotted by the truck's driver.
As the Driver tries to grab Fencer, Vinnie and His Hench-Cats open the truck's back doors absconding with gobs of fishes and runs off, passing up Foofur's group, who goes to locate Fencer, who still has the keys, but when the Driver gets rough, Foofur's group help Fencer escape with His life. Fencer, realizing that He dropped the keys, tries to go back, but Foofur stops Him, making Fencer explain that He's trying to pass His tests, and leaves, after thanking Foofur's help. Foofur then has a plan and it will involve the Aquarium. later, the the Cat Pack's hideout, Fencer explains that He dropped the keys in the chaos. Vinnie explains that Fencer can make up, so long as Fencer locks up the Aquarium's Guard Dog.
At the Aquarium, The Guard Dog thanks Foofur and the others (composed of Louis, Fritz-Carlos, and the Rat Brothers) for taking His place for the day. At Night, The Cat Pack and Fencer arrive at the Aquarium, with Fencer going inside through the mail slot. In the Aquarium, Fencer spots the dog and lures Him in a closet. As the Cat Pack listen to hear Fencer getting clobbered, Fencer shouts, startling them. With the Cat Pack inside, Vinnie disdainfully says that Fencer is now a part of the Cat Pack. at a room of fish tanks, Louis' barks scare the Cats, and the Rat Brothers use the scary dog picture to disorient the Cats even more. Vinnie berates Fencer for not making sure the Dog was locked. Vinnie then opens the door to the closet, which still had the Guard dog, scaring the Cats into a pool. Vinnie then says to the Guard Dog lying that Fencer made them get inside, and They only kept Him around for laughs. The Guard Dog, who was really Foofur, in clothespins and rubber bands, asks Fencer what He'll respond. The Cat then declares to Vinnie that the next time The Cat Pack messes with Him, Fencer has real family. The next morning, as everyone enjoys the pool, Fencer who is wearing sunglasses and on an inner tube, says that He's in His element, and the pool is cool, since the Dogs can't get Him out. underwater, however, The Rat brothers are swimming as well, as They plan to prank Fencer yet again...
- When The Cat Pack with a lot of fish ran past Foofur and the others, Vinnie's eyes were white.
- After the Rat Brothers scare Fencer, Chucky laughed and spoke in Baby's voice.
- When the Cat Pack is startled by Louis' growling, The Gray one, the Blue one, and Fencer's mouths didn't move.
- At the end, when Annabell is seen coming out, Her neck ribbon is missing.