The subway commissioner refers to the kids helping with the "subway ghost problem we had a while back." This probably refers back to I'll Take Manhattan.
The first Scooby-Doo story runs through the time-tested characterization of the gang courtesy of Scott Cunningham. The mystery rails against the usual simple but winning real-estate fraud in favor of a more serious crime which nicely clouds the motive and therefore the conductor of this ghostly exercise.
Mr. Cunningham gives weight to the story via a false history no doubt based on several stations of subway lore. He creates a sense of place by including touches distinctive to the environment and diverging to false leads.
Joe Staton must never leave this book. Apart from evolving an eerie subterranean atmosphere, he gives the crew variety in stature, ethnicity, body types and expression. His work on the gang never fails to impress. Daphne is cute and confident. Freddie is stalwart and walks the walk of a born leader. Scooby and Shaggy are not just a comedy team amid straight detectives. Both are shown to be loyal to each other, and its through this trait, a scene of suspense surprises and grips the reader.