 Sister Bertrille is looking after Pepe, a chimpanzee, as a favor to Dolores, one of Carlos  girlfriends. Pepe s arrival at the convent coincides with a rash of thefts in the neighborhood, thefts of small, rather insignificant trinkets. The latest theft is of Captain Fomento s watch right in the convent. Yes, the thief is Pepe. The captain thinks that it is someone in the convent. Sister Jacqueline, who finds the stolen items in Sister Bertrille s closet (Pepe s hiding place), reports such to the Reverend Mother and based on Sister Bertrille s behavior, Sister Jacqueline and the Reverend Mother believe Sister Bertrille suffers from kleptomania. Sister Bertrille is oblivious to Pepe s thieving ways until she sees him take off with a candlestick. As Sister Bertrille chases after Pepe, Sister Jacqueline, the Reverend Mother, Captain Fomento and Sgt. Salazar chase after Sister Bertrille. It isn t until Dolores returns to retrieve her thieving pet monkey that the truth is revealed to all.