I'll be honest, when I first realized that Ten was a retelling, I wasn't expecting it to be that great. It was especially groan-worthy when Megan "pulled out a copy of the Facebook invite," because it seemed like a halfhearted attempt to inject teen culture into the Christie story. But once the mystery took off and characters were fleshed out, it became a gripping thriller. The ending also involves a new twist that I did not see coming, so kudos to McNeil.
I think teens who aren't familiar with the Christie thriller will enjoy it the most, but those who have had exposure to the classic will appreciate the new ending. The book trailer for Ten is the DVD played in the novel. It's actually pretty great and playing this would be a simple way to book talk this novel.