When Amber Hewerdine consults a hypnotherapist as a desperate last resort, she doesn’t expect that anything much will change.

She doesn’t expect it to help with her chronic insomnia …

She doesn’t expect to hear herself, under hypnosis, saying words that mean nothing to her: ‘Kind, cruel, kind of cruel’ - words she has seen somewhere before, if only she could remember where …

She doesn’t expect to be arrested two hours later, as a result of having spoken those words out loud, in connection with the brutal murder of Katharine Allen, a woman she’s never heard of …