Verhoef seamlessly interweaves the narrative strands of her tale of intrigue, placing the reader in close proximity to both crime and crime fighter. She opens with police inspector Miriam de Moor, who has just discovered that her brother’s widow has taken up residence in a luxury penthouse. Miriam’s brother died six months previously after a fall down the stairs. She suspects that his death may not have been an accident and that her former sister-in- law may somehow have been involved.

That same morning, Hennequin Smith starts work as a maternity nurse at the home of brand new parents Didi Stevens and Oscar Vos. Didi is confined to a wheelchair due to pelvic problems related to her pregnancy and the difficult birth has left her barely able to take care of her newborn child. She is almost completely dependent on Hennequin’s help.

Not only is the nurse an impostor – her qualifications are fabricated, her work experience a pack of lies – but she is also a sadist with her mind set on a single purpose: to inflict endless suffering on both mother and child. She takes subtle advantage of hard-working Oscar’s reluctance to accept his role as a father and of Didi’s distress in the face of her physical incapacity.

Miriam conducts her investigation on her own time, knowing that she faces summary dismissal if her bosses ever find out what she’s up to. Despite the risks, she vigorously pursues her inquiries and little by little begins to uncover the past that Hennequin has gone to such pains to conceal. She discovers the maternity nurse’s true identity and brings her quarry into sharper focus by questioning former teachers, guardians and institutional directors. Eventually Miriam manages to contact Hennequin’s father, who refuses point-blank to cooperate with the one-woman investigation.

In this claustrophobic thriller, Esther Verhoef demonstrates her complete mastery of the genre, steering her plot expertly towards its unexpected climax without ever giving away more than is strictly necessary.