The lead voice work in this episode is performed by Frank Welker, who voices Ray Stantz and Slimer. Recurring cast includes Dave Coulier as Peter Venkman, Buster Jones as Winston Zeddemore, Maurice LaMarche as Egon Spengler, and Danny Mann in supporting roles. Recording sessions took place on July 6 and 8, 1988; LaMarche and Coulier recorded specifically on July 8.
Mike the Mail Man arrives outside the Firehouse carrying the latest issue of Flex-O-Man (issue #315), a comic published in-universe by DIC. Slimer is delighted and retreats to the sleeping quarters to read, but Peter Venkman's snoring makes concentration impossible. Slimer moves to Egon's lab, where Egon is testing his Dimensional Inverter. The device accidentally reduces Slimer's Stay Puft Marshmallow Man doll to ashes and fries the comic book. Egon, absorbed in the experiment's success, offers little sympathy. Slimer decides to build a private clubhouse on the Firehouse roof.
Up on the roof, Manx has already staked out the area and drilled a small hole that allows him to siphon food directly from the kitchen below via a straw. When Slimer begins building a frame directly over the hole, Manx launches a series of escalating pranks: he swaps Slimer's real hammer for a Ha Ha Hammer gag toy, sending Slimer bouncing into the gutter; he enlarges the hole and attaches a vacuum cleaner to steal the refrigerator's contents; and he plants a bomb hidden in a flower arrangement outside the clubhouse door. Each scheme backfires. The bomb's fuse is snuffed when Slimer waters the flowers, and when Manx uses a blow dryer to relight it, the cord runs out and Manx is blasted off the gutter himself.
Manx's final gambit is to commandeer a rooftop crane and swing a wrecking ball at the clubhouse. Slimer spots a nearby billboard featuring a giant tennis racket prop, grabs it, and bats the wrecking ball back. The crane spins away and drops Manx into the middle of Mayor Lenny's dedication ceremony for a new sculpture garden. The Mayor assumes Manx is simply an unusual modern sculpture. Slimer finally settles in to enjoy some peace, only to have all four Ghostbusters show up: Peter wants a nap, Egon wants quiet to think, and Winston wants to watch the game.
Several aspects of this episode deviate from the established Firehouse layout seen elsewhere in the series: