A young teacher who is having an affair with a married man — her pupil’s father. The man’s wronged wife — a true-crime writer. The crime she writes about — the murder of an adulteress. In her debut, A Child’s Book of True Cime, the Australian novelist Chloe Hooper may not be a master architect of suspense on the order of Ruth Rendell or Patricia Carlon, but give her credit for assembling some intriguing ingredients. Though her narrative ultimately bogs down in thin plotting and a repeated literary conceit (see the title) that was probably more fun to write than it is to read, Hooper has already found a voice — smart, admirably discomfiting — that makes one eager to see what she’ll do next.