Blood Ransom by Sophie McKenzie
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Blood Ransom is every bit as exciting as its predecessor, Blood Ties. Rachel and Theo are living in different countries under a government protection program. They keep in touch via a weekly internet chat, but when Rachel misses a session, Theo gets suspicious. It turns out Elijah Lazio, evil genius mad scientist, is at it again, and this time he's after Rachel. Each chapter ends in a cliffhanger and you won't be able to stop turning the pages. Give this one to fans of Cherub. Grade 6+