Big Al Caesar was a mobster at some point during the 1930's or 1940's, and met his end under unspecified circumstances. He died failing to achieve his greatest heist, a treasure called The Maltese Monkey (also the title of the episode). During the start of the episode, two present-day mobsters, Fat Man and The Rabbit, attempt to use a crystal ball to summon the ghost of Big Al to aid them in finally acquiring the Monkey. In the meantime, the Ghost Busters-Eddie Spencer, Tracy The Gorilla, and Jake Kong, receive word from their mystery employer, Zero, that this caper is about to happen. Zero indicates dire but vague consequences should the trio succeed. The Ghost Busters travel, albeit with great reluctance on the part of the cowardly Spencer (not that any of our heroes are that stout-hearted) to a cemetery where Fat Man and The Rabbit succeed in summoning Big Al, who looks just like Eddie Spencer, down to his clothes. Big Al, who looks fully alive and able to travel, quickly agrees to aid the two. Big Al speaks in a slightly Godfather-esque voice, but otherwise also sounds just like Eddie.
The heroes, hoping to foil this plot in the act, follow the villains to their lair, an abandoned castle on the outskirts of their unnamed town. Using Eddie's lookalike status and a badly disguised bowling ball to sub for the crystal ball, the Ghost Busters trick Fat Man and Rabbit into believing Eddie is Big Al, and then 'summon' Jake Kong and Tracy The Gorilla, as Big Al's ghostly muscle. Big Al spots all this and replaces Eddie on the trip to the museum where the Maltese Monkey is kept. Proving not much brighter than the dim Spencer, Kong and Tracy are fooled into helping Big Al, who only reveals himself after he finally obtained The Maltese Monkey. Returning to the Castle, heroes and villains fight over possession of the stolen treasure until the Ghost Busters corner Big Al alone, using their Ghost De-Materializer Ray to send him permanently back to the afterlife. Fat Man and Rabbit are captured when Tracy uses the fake crystal ball to literally bowl them over. While The Maltese Monkey is returned to its rightful owners, the incompetent heroes mess up when Spencer and Tracy mistake the actual crystal ball for a bowling ball and shatter it.
- Being the villain of the show's first episode, Big Al is technically the first ever villain to face down a group of heroes named the "Ghost Busters".
- He was played by veteran comedian and voice actor Larry Storch, who also played series regular protagonist Eddie Spencer. Storch is most notable, villain-wise, as the first-ever animated voice of The Joker.
- Given the show's slapstick nature and low-budget antics, both characters also dressed exactly the same.
- According to Wikipedia, these Ghost Busters were the name inspiration for the original 1984 film, as well as being the premise inspiration for the Filmation animated Ghostbusters, where Tracy The Gorilla joined the sons of the Ghost Busters from this show to fight villains such as Prime Evil.
- The other Human Ghost Buster was played by Storch's old comedic partner, Forrest Tucker from F-Troop, also seen in the cheesy horror film and MST3K classic The Crawling Eye. Fat Man and The Rabbit were played by Johnny Brown (Bookman from Good Times) and character actor Billy Barty, also known as the evil assistant to Sid & Marty Krofft's Dr. Shrinker.
- Big Al Caesar's name seems like a combination of the real life gangster Al Capone and Little Caesar, a memorable film role for cinema legend Edward G. Robinson, and partly based on Capone's life and times.