Robson wraps up her highly inventive, often convoluted Quantum Gravity series with this complex tale that brings all the different elements of the story together in a satisfactory conclusion. The boundaries between worlds have grown so perilously thin that it is possible to end up in the wrong one by mistake. Dead people are reanimating resulting in more then a few “accidental” murders as loved ones struggle to cope. Surely, the end of days is near and Lila Black would be content to simply allow events to run their course but for the nagging suspicion that she may have inadvertently triggered them in the first place.Lila, who is as much metal machinery as human, is married to Zal, an elven musician who has become an animated demon soul who takes form in firelight and can no longer hear music and Teazle, a demon who is well on his way toward becoming an angel. As they struggle to make their three-way marriage work, trust becomes a rare commodity while an ancient evil stalks through the landscape and Lila’s mind.
The way this stellar urban fantasy unfolds is much like following a mobius strip as it twists and folds back upon itself while never failing to deliver plenty of surprises. The relationship between Lila, Zal and Teazle has been a fascinating centerpiece of the overall story and plays a large role in this last book of the series. Readers just discovering Lila’s adventures will need to start at the beginning as the complexity does not lend itself to simply picking up the story mid-way and certainly not with this book. The addition of Zal and Teazle’s perspective adds additional depth to an already outstanding rollercoaster ride that will leave readers feeling dizzy.