I liked the tone; in particular I thought the dialogue sounds a lot like the Amelia Peabody series. Abigail needs some fleshing out to make her wholly believable, Jackaby is amusing just as he is. Jackaby's house is almost a character itself, with the toad you must not stare at and the pond on the third floor. The villain was instantly obvious, at least to me. It doesn't break any new ground in either genre - one blurb says Dr. Who meets Sherlock, and he wasn't wrong, you can almost see the boxes getting checked off - but IMO it fits its intended YA audience very well.
