From the back cover:
"How can she be in two places at one time?
"Laurie was at home, but her boyfriend swears he saw her on the beach with another guy. Her family insists they see her coming and going when she's been out of the house for hours. Who - or what - is taking over Laurie's life?"
Stranger is a good, plot- and writing-tight young adult novel. There aren't a lot of twists in this engaging thriller, but it's a solid read by an author who's consistently worthwhile.
The television movie version aired stateside on August 29, 2009.
Alexz Jones played Laurie Stratton/Lia Abbott. Andrew Francis played Jeff Rankin. Emile Hirst played Alexis Stratton. Bruce Dawson played James Stratton. Grace Sherman played Helen Tuttle. Beau Mirchoff played Gordon Lambert. Nhi Do played Darlene.
Catherine Hicks played Shelley Stratton. Bill Marchant played Bill Abbot. Joanne Wilson played Ellie Abbot.
Jeff Renfroe directed the film from a teleplay by Jamie Pachino and Eric Tuchman.