The comic's name is a parody of the film The Night of the Living Dead.
The comic in the book starts on a late Friday afternoon with the Lunch Ladies cleaning up the cafeteria (They note "Waste not, want not!" as they dump half-eaten food into a pot of stew). The Janitor, without noticing, locks the school up for the weekend. Trapped inside, the Lunch Ladies are forced to eat their own foods to survive. The Janitor appears after the weekend and finds the Lunch Ladies dead (victims of their own cooking, apparently). The Janitor says "Oopsie Daisies!" when he finds out.
He then takes them up a hill to bury them and does so, but they come back to life as zombies (because the hill was haunted and nothing dead should be buried there). The Zombie Lunch Ladies attack the school (because they were hungry for brains (actual ones) and they just attacked the gym teacher, apparently), but Captain Underpants appears and attempts to give them wedgies. However, the Lunch Ladies feel no pain due to them being undead, and a fight begins. Captain Underpants leaps onto the top of a building and the Zombie Lunch Ladies follow. (They run faster than their "Runny Meatloaf Gravy", they are more powerful than the stench of their "Sloppy Joe Casserole", and they can leap tall buildings with the gassy after-effects of their "Texas Style Three Bean Chili Con Carner".)
Soon, the Lunch Ladies have our hero right where they want him on the roof, but Captain Underpants wraps them up in toilet paper (known as, "The Toilet Paper of Justice) that he got by pressing a button on his "Utility Waistband". Unfortunately, they pull salsbury steak sauce out with a trick up their sleeves and pour it on the toilet paper, and go after Captain Underpants by pushing him off the building, but the Zombie Lunch Ladies also fall off. Captain Underpants uses the rest of the Toilet Paper of Justice to swing to safety. The Zombie Lunch Ladies, however, fall into one trash can each. Captain Underpants sings his trademark, "Tra-La-Laaaaa!", as the comic ends.