Private desires a promotion after Skipper forbids him to look at a joke contained in a classified mission file. Skipper agrees to such a promotion, but only if Private can pass a one-on-one survival test against "the most fearsome beast in the concrete jungle" on the streets of New York, where he is soon taken. Left alone in an alley, Private is passed a cassette player by the other penguins containing audio instructions on how to outwit this enemy. However, Private's test is soon interrupted by the arrival of the lemurs, who believe they are on a camping trip and consistently get in the way of Private trying to follow the tape's directive. Eventually, Kowalski reveals the specificity of the enemy Private must confront through song: an evil, ghostly city bus notorious for making roadkill out of animals known as the "Graveyard Eight". In order to pass his test, Private must confront the bus and bring back a souvenir from it. This inevitable confrontation occurs when the bus comes by while the lemurs are "sewer fishing" and entangles their fishing lines in its bumper, taking them with it as Private races to catch up. Julien soon gets himself free, but goes inside the bus with Private to look for something sharp to free the others, which Private accomplishes with the name badge of the driver, a short, elderly woman with a deep, demonic voice. For his successful encounter with the Graveyard Eight, Private is promoted to Private First Class. He is finally able to read the joke, but in the end, he doesn't quite understand it.