"The Little Merhog" is the fifty-sixth episode of the Adventures of Sonic the Hedgehog television series. Despite it being produced as the fifty-sixth episode, it originally aired as the sixtieth episode during the show's original run.
While fishing, Sonic and Tails accidentally hook Merna the Merhog. She says she needs help, so Sonic and Tails get their scuba gear on and follow her into the sea.
Under the sea in an octopus submarine, Captain John Paul Memo and his sidekick Lt. Bananas plan to demolish the fish city to build condos and then charge the fish rent to live there. Sonic quickly anchors the squid sub. Captain Memo has the squid tentacles grab Sonic, Tails and Merna, but Merna calls some electric eels to come and help them out. The Sub makes it to Mertopia where it begins to destroy things. Sonic and Tails escape promising that they will save the city.
Sonic and Tails go to Dr. Robotnik's Lair where they trick Robotnik into wanting to stop Captain Memo. Grounder builds a submarine that resembles himself. Scratch re-designs it to look like him then Robotnik re-designs it to look like him. They get in and start firing missiles at Captain Memo's sub. Captain Memo fires back.
Sonic and Tails return to Mertopia and tell Merna and the Queen that the city is saved. Scratch and Grounder spy on them from inside a bubble and figure out it was all a trick. They tell Robotnik and he makes a truce with Captain Memo.
While Sonic and the Merhogs celebrate, Robotnik attacks Mertopia with Captain Memo's army. Merna and Sonic dive underwater and she calls on all the fish in the sea for help. All the sea animals come and sink both villains' ships. Robotnik gets eaten by a shark and Captain Memo gets tied up and taken away by a squid officer. All the Merhogs celebrate and Sonic and Merna share a kiss.