Plot
A full moon rises over Ireland and a Bog Hound emerges from a pool, howls at the moon, and dives into the Atlantic. In New York City, the Ghostbusters are clearing the last of several Irish ghosts at the Waldorf Hibernia hotel, where Mayor Lenny has invited every important Irishman in the city to a St. Patrick's Eve dinner. Egon tracks the ghost with his P.K.E. Meter, Winston corners it under a glass bowl, and Egon traps it. A woman arriving at the banquet screams at the wreckage inside, and Peter, mistaking her for a ghost, fires in her direction and vaporizes her dress.
The woman is the Mayor's wife, and the Ghostbusters are arrested. Back at the precinct, Lieutenant Frump mocks them in their cell. Deputy Police Chief O'Malley visits with an offer: help him and he will drop the charges and pay for the dress. O'Malley explains that long ago the O'Malley clan stole a pot of gold from a Leprechaun, who cursed them so that on a full-moon St. Patrick's Day a Bog Hound would rise and carry off the head of the clan. With a full moon falling on St. Patrick's Day and himself the current head, O'Malley fears he is the target. He produces a tuft of the Hound's distinctive green fur handed down from his great grandfather, who escaped the creature. Egon is skeptical, but Peter is interested in getting out of jail.
The Hound reaches New York and spooks two old men on a park bench. O'Malley insists the only way to defeat it is with a four-leaf clover. Egon, convinced science can beat the monster, goes off alone and is overwhelmed: his Proton Pack fails at the Bronx Zoo, he ends up in a tree full of wild cats, and he escapes only by distracting the Hound with a game of fetch.
The rest of the team scours the city for a four-leaf clover. Winston works the florists, Peter searches the Botanical Gardens, and Ray goes to Central Park, where a police officer mistakes him for mocking his Irish heritage and throws him in a garbage can. Peter finally finds a clover at the Botanical Gardens, but back at the firehouse Slimer eats it. The team decides to simply blast the Hound with their equipment.
The Hound catches up with O'Malley and the Ghostbusters at the Police Benevolent Society float during the St. Patrick's Day Parade. The creature is too agile for the Proton Streams, and Winston and Ray's packs are disabled when the float collapses onto them. With the Hound cornering O'Malley, Ray, and Winston in an alley, Peter grabs the clover from the Mayor's wife's corsage and confronts the Hound, only to find the clover is plastic. Egon captures the monster anyway when it blindly runs over an open trap. The parade's directors name the Ghostbusters honorary Irishmen, and the Mayor's wife, serving as honorary grand marshal, takes her revenge by pinning Peter.
Production
The episode was recorded on August 27 and 29, 1986, with Laura Summer recording alone on August 29.2 Michael Edens said the story grew out of New York's heavily Irish police department and the St. Patrick's Day Parade.3 He had originally wanted to use a Banshee, but one had already appeared in "Banshee Bake a Cherry Pie?"4 Edens came across the legend of the Black Dog in Celtic mythology while researching the episode and renamed the creature a Bog Hound because it sounded better.5 The Bog Hound's green fur and general character bear some resemblance to the Cù Sìth, a giant supernatural hound from Scottish and Irish myth said to be dark green in color and associated with carrying souls to the afterlife.
The design of the Bog Hound was loosely based on the Terror Dogs from the original Ghostbusters film.16 The two old men spooked on the park bench are an homage to similar characters from "The Bullwinkle Show."7
A June 30, 1986 script included one more scene of Egon chasing the Bog Hound, set at the Natural History Museum and involving the disruption of a Tyrannosaurus rex skeleton.8
Notes
Deputy Chief O'Malley's story has his clan cursed by a Leprechaun, possibly the same one later encountered in the Extreme Ghostbusters episode "The Luck of the Irish," which also features a minor character with the surname O'Malley.
The Bog Hound behaves very much like an ordinary dog throughout the episode: it chases cars, is drawn off by a game of fetch, and corners prey in an alley rather than using any supernatural cunning. Its weakness to a four-leaf clover is confirmed by Ray's citation of Chapter 27 of Tobin's Spirit Guide, titled "Botanical Specific Avoidance in Spectral Manifestations."
When his Proton Pack fails at the Bronx Zoo, Egon tries to stop a lion with the word "Ungawa," the term Tarzan used to communicate with animals. He then references Johnny Weissmuller, the best known of the actors to play Tarzan. Back at the firehouse, after Slimer eats the clover, Egon compares the ghost's appetite to that of a Cuisinart, a brand of kitchen appliances.
The Bog Hound makes later appearances in IDW Publishing's comics continuity: a Bog Hound head is mounted inside Wander Hills Orphanage in Ghostbusters Issue #2, and the creature makes a non-canon cameo in Ghostbusters Volume 2 Issue #20.
