TPU色母和PA6色母的区别This is based on the novels of Holly Jackson.　　Five years ago, schoolgirl Andie Bell was murdered by her boyfriend Sal Singh. Case closed. The police know he did it. Everyone in town knows he did it. But smart and single minded Pip Fitz-Amobi isn't so sure and she’s determined to prove it. And if Sal Singh isn’t a murderer and the real killer is still out there, how far will they go to keep Pip from the truth?