This page contains content that is considered "level 2 canon" and may be contradicted by the TV series.
Steven and the Gems set sail on the Gem Sloop to find and retrieve a gem artifact in a remote location inaccessible by warp pad. They discover that the artifact is guarded by a territorial gem monster, who shipwrecks the Crystal Gems in their first attempt to get the artifact. Luckily, Onion and his dad Yellowtail are out on a fishing trip and happen upon the Gems at just the right time.
The comic begins with Steven walking out of Funland Arcade with a new G.A.L.S. figurine: Fisherman Gal. He walks along the boardwalk admiring it, an action that results in a collision with Onion and the subsequent loss of his figurine. Onion catches it before it can roll into the ocean and hands it back to its owner.
Steven notices all of the fishing gear that Onion had dropped too, and asks him what his plans are for the day. This question is soon answered when Yellowtail pulls up to the dock on his boat. Steven helps Onion collect his fallen gear for a fishing trip and bids them farewell.
He soon realizes that he wants to go fishing too. An opportune moment presents itself when Steven walks onto the beach to see the Crystal Gems preparing the Gem Sloop for a mission. They explain to him that they need it to reach a Gem artifact in the ocean that is inaccessible by Warp Pad. He excitedly asks if he can join them on the mission and, after receiving permission, grabs some items, including an impromptu fishing rod fashioned out of a stick and dental floss with gummy worms serving as the bait.
They sail towards their destination and Steven is given time to fish. He does so (without luck) until the sloop arrives at a small island that houses the artifact - the cabouchon circlet. The Gems start to scale the side of the island to retrieve it but are interrupted by an ominous snap sounding from Steven's fishing rod.
The culprit rises out of the ocean and towers above them, revealing itself to be a Red Eel Monster. It grabs the circlet in its mouth and dives back under the water.
They proceed to fight the monster but, in the process, the sloop is destroyed and the Gems are simultaneously knocked into the water. Steven guiltily realizes that the gummy worms he had been using for fishing bait had unintentionally drawn the eel monster to them.
The Gems reassure Steven that it wasn't his fault because he couldn't have known what would happen. Amethyst asks Garnet what their plan should be. Before she can reply, Yellowtail and Onion appear in their boat and pull them on-board. Steven explains the situation to them and asks if they can assist in catching the aquatic monster.
With Onion and Yellowtail's consent, a new plan is formulated. A gummy worm is used as bait to draw the eel out of the water again, allowing the Gems to launch an assault. It soon becomes apparent, however, that their attacks are ineffective. Fortunately, Onion is able to fire a harpoon into the monster to defeat it.
As Steven is bubbling the corrupted gem the cabouchon circlet sinks underwater. Garnet reluctantly volunteers to retrieve it. In her absence, Onion, Yellowtail, and Steven fish as Pearl and Amethyst gather the pieces of the gem sloop to rebuild it.
The sun begins to set when Garnet finally resurfaces. She sends the circlet back to the Temple - signifying the successful completion of the mission. The group celebrates with some fishing and the comic ends with Steven finally getting a bite.
- While coming up with ideas for this issue's story, Grace Kraft decided to center the plot around the Gem Sloop and work backwards on the rest of the details from there. 
- The design for the Red Eel monster unintentionally "ended up looking like an aquatic cousin of Centipeetle, a Sea-ntipeetle if you will." 
- Onion and Yellowtail were included as an integral part of the mission to reflect how Steven's human-half and his interactions with 'townies' are just as important as the interactions related to his gem-half. 
- As noted by Steven, the fisherman gal figurine bears a resemblance to Yellowtail, sharing the same yellow raincoat and hat.
- The Red Eel Monster's design is "inspired by Seadramon from Digimon and the Unagi from Avatar: The Last Airbender." 
- Steven purchases a G.A.L.S. figurine. This brand of toys was first seen in "Onion Friend".
- Garnet picks Amethyst up and throws her at the Red Eel Monster. This maneuver was first shown in "Laser Light Cannon" where Garnet throws Amethyst at the Red Eye.
- The Gems reference the events of "Cat Fingers" when they mention that the Gem Sloop hasn't been used in a while and that Steven has grown enough to go on a seafaring mission with them.
- Onion uses a harpoon gun to defeat the gem monster. He first used the weapon in "Bubble Buddies".
- Before Steven drops his Fisherman Gal figurine, her raincoat is yellow. When he picks it up again her raincoat turns white.