Penelope Crumb's best friend Patsy Cline Roberta Watson is becoming best friends with another girl in class, so Penelope decides she needs to win her back.  Compliments and presents fail—and Penelope is afraid she'll lose Patsy Cline forever, so she decides to swipe Patsy's necklace and start a secret museum to remember all the people she cares about, in case they leave her too.  But stealing turns out not to be the best plan, when Grandpa Felix calls the police about his missing camera, forcing Penelope to confess. Now she's lost both Patsy Cline AND her museum.  But in the end she makes a huge personal sacrifice to repair her friendship with Patsy and finds out that drawing pictures—what she likes to do best!—is a way to make a personal museum that doesn't involve any sort of stealing.