Playing with Fire is the third book in the Sweet Valley High Series.
Jessica Wakefield finally succeeds in snaring her dream boy, Bruce Patman, despite her actions at the Fall dance in the previous story, Secrets. He seems to be attracted to her, and he is devoted, or so she thinks.
Her relationship with her twin sister, Liz begins to suffer, because Liz does not trust Bruce one bit. She never had liked him due to his snide and arrogant ways, and that was a sore spot with Jessica, who believed that anything Bruce did was perfect.
However, Jessica finds his attention waning later on; and he comes up with an idea to help her with her floundering Chemistry grade. She convinces chubby Robin Wilson, a girl who thinks that Jessica is her best friend (she isn't), to steal the answers for the upcoming Chemistry test, and to give them to Emily Mayer, the drummer for the Droids. To Jessica's fury, she still fails the test; and later discovers that the Chemistry teacher, Mr. Russo, had changed the test, and the stolen answers didn't help her at all. Emily however, couldn't live with having cheated, so she confessed. Russo yelled, and gave her detention and some extra work, but Emily's conscience was clear.
After the Chemistry issue, Jessica's issues with Bruce's constant lying became more pronounced. Liz had a confrontation with John Pfeifer who had extended Liz's Eyes and Ears column with a note about Bruce being in a road rally, and it served to confirm her fears about Bruce's lying to Jessica. At his 18th birthday party, Bruce played the devoted boyfriend, and then had the party moved to Guido's Pizza Palace. However, Bruce's lies finally caught up with him.
Using the cover of his sick grandmother, Bruce leaves the party to go and pick up someone; Jessica, unwillingly, goes with Elizabeth and Todd, to look at the stars, and then they go back to Guido's where Jessica sees Bruce with Aline Montgomery, a girl that Bruce was seeing behind Jessica's back.
Infuriated, Jessica takes a pizza and throws it at Bruce; then proceeds to dump a pitcher of soda all over his head. She then lets the air out of all four tires of Bruce's black Porsche, and then goes on a date with Winston Egbert.