Marlene of the Deep is a comic book that belongs to Ed. It was first seen in Little Ed Blue where Eddy was reading it to Ed to try to cheer him up. Nothing has really been revealed about the plot of the comic except for one quote: "Its tentacles tightened, sucking the marrow–". But before Eddy could finish the sentence, Ed slammed the book into Eddy's face, turning it into a comic strip. However, the sound of the title and the quote suggests that the plot may be about a colossal tentacled aquatic monster and has a horror/sci-fi plot.
The front illustration of the comic book is mistakenly placed on the back side, making it look like manga (the Japanese equivalent of comics, which are read right-to-left) instead of an American comic book.
- The title may be a reference to Marlene Robinson May, a sheet director and supervising animation director for much of the series.