They might also like [[Changeling by Steve Feasey]], about Trey, the last living werewolf. It's pacy and direct and the central character is wolfishly attractive. No supernatural, but [[Brainjack by Brian Falkner]] is a pacy action thriller about a teen computer hacker and a rather scary, self-aware AI. If they liked the gadgetry in ''Department 19'', they'll like it.
[[Will Hill's Department 19 Books in Chronological Order]]
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