Sister Rosette, an exorcist for the Magdalene Order, is dispatched late one night to exterminate a troublesome devil. But things get a little out of hand, and she ends up destroying a building! So the following day, as always, she has to write a letter of apology. Sister Kate uses this incident to suggest Rosette's partner, Chrono, might be the problem. But Rosette quickly blows this idea away as so much hot air. Rosette and Chrono then get ordered to the New York harbor, and this time they have to play hide-and-seek with a monster that's stowed away in a freighter's cargo!