The episode opens up at the Pac-Land water tower. The ghosts' latest scheme to get to the power pellet forest is to go through the water tower's pipes that lead to the forest. Unbeknownst to them, two workers reroute the water to the crocodile cage at the Pac-Land Zoos due to the power forest not needing anymore water. Pac-Man happens to be at the zoo and feeds the crocodiles power pellets to chomp the ghosts. This sends the ghosts' now disembodied eyes back to Mezmeron's lair.
The ghosts return to the lair and try to get past Mezmeron without alerting him, but they fail. They begin blaming each other for the failure of their plan but Mezmeron tells them to shut up. Frustrated with their incompetence, Mezmeron decides to find the power forest himself.
At the power pellet forest, in his security station, Pac-Man is juggling power pellets while on a bucket when Grump comes in and tells him to get back to work. Grump attempts to juggle the power pellets but fails when Pac-Man returns to retrieve his hat. Meanwhile, Mezmeron and the ghosts are hiding under bushes in an attempt to find the forest. Clyde sends Inky to find the forest, but when a giraffe tries to eat the flowers on his head he runs in terror and falls over, causing Mezmeron to trip over him and set off an alarm. Pac-Man calls a red alert, and the crew gets to work in protecting the forest. Mezmeron sees Pac-Man and sends the ghosts after him, but they get pelted with catapulted power pellets, then Pac-Man sends troops to chomp the ghosts and at Mezmeron, sending them running back to their lair.
Mezmeron, with the bottom half of his robe chewed up (revealing a pair of green polka-dotted boxers), puts himself into a new robe (the ghosts' disembodied eyes accidentally find themselves in Mezmeron's spare robes before being yelled at), and hatches a new plan to get the power pellet forest undetected - tunnel his way underground to retrieve it. The ghosts begin drilling the tunnel to the forest, and while doing so spot tree roots. Inky uses a periscope and he sees what he thinks is a power pellet tree, but it's actually Pac-Man holding an image of one underwater, so when Pinky goes to check, water gets sucked into the tunnel and washes the ghosts and Mezmeron back to their lair.
The ghosts begin digging another tunnel while Pac-Man, using a detector, begins digging underground, falling into their tunnel. The ghosts chase Pac-Man who attempts to run away, but they overtake and chomp him, weakening him. Mezmeron emerges from the ground with the ghosts and demands the citizens of Pac-Land tell him the location of the power pellet forest within one minute, showing a weakened Pac-Man to prove he will be of no help. Ms. Pac-Man comes by and agrees to tell them the location, despite Pac-Man telling her not too. Mezmeron is overjoyed to find the forest at last, but he soon finds out Ms. Pac-Man tricked him and what he thinks are power pellets are actually hornets. Pac-Man and his wife eat some power pellets and chomp the ghosts, while Mezmeron gets chased away by a swarm of angry hornets. The episodes ends with Pac-Man saying was "on top" of Mezmeron the whole time, causing the ground he's standing on to collapse.
- The name of the episode is a pun on the famous book "Journey to the Center of the Earth".
- When Pac-Man falls over weak after the ghosts chomp him, the black rim on his hat disappears.