Lia and Ali are trained to use their elemental weaving powers to destroy burl beasts - mindless, bloodthirsty monsters created when the threads of their world tangle together. Their secret? They themselves are a burl beast: twin sisters, forced to share one body. Quiet and reserved Lia controlling by day. Outspoken and abrasive Ali leading by night.

When news arrives that an elusive criminal is creating bespoke burl beasts by practising the illegal magic that could finally separate them, the girls jump at the chance to join the team sent to investigate. But as the girls get closer to their new flock and, more importantly, two different boys, it becomes harder to hide who - or what - they really are.

Delving deeper into the dangerous world of flesh-weaving and political intrigue, the girls get closer to the answers they so desperately seek. But is the price of their separation truly worth the risk?