Jake Djones is caught up in the work of the Bureau of History Keepers when his parents, who have secretly worked for them all these years, disappear while on a mission. He joins forces with other youngsters who work for the Bureau, and together they travel back through time, working to foil a world-destroying plot by their vicious archenemy Zeldt. On the way, Jake finds his parents and learns more about the history of the others. Meanwhile, back at the Bureau, a traitor is unmasked who has been feeding information to the enemy. But someone else has an undetected secret.

The very least you can say about this book is that there’s nothing offensive in it. If you have more or less a taste for time-travelling heroics mixed with a modicum of intrigue and double-dealing and a smattering of very mild romantic interaction, you’ll probably be entertained. There’s adventure and there’s historical interest and there’s an insanely villainous archenemy (archenemy family, in fact) with a plot to nip the Enlightenment in the bud. (These time-travelling bad guys – what will they think of next!?)

I can’t say I actively dislike it. But somehow the whole confection fails to satisfy. Each of the main characters is well-defined and plays his or her part well enough. But they so rarely rise above their one trick. Nathan is a foppish dandy with a penchant for costume-based wit, as well as a competent History Keeper. Charlie is a young genius and can produce good food wherever and whenever he is. Topaz is beautiful and as competent as her brother Nathan. Jake’s aunt, Rose, is friendly and ditzy and a little past her prime as an agent. It’s all there, but there’s too much plot, perhaps too many characters, and certainly too little heart.

Tim Golden is a computer programmer living in London. This review first appeared on goodtoread.org.