"Killing Mum" by Allan Guthrie is a nicely crafted and seriously intriguing novella about Carlos Morales. Carlos runs a tanning studio in Edinburgh. Actually, the tanning studio is only a front for his real business, which is arranging contract killings. People send him money, and he subcontracts the actual killing to an associate. Carlos has a problem, however. The associate he used while building up his business has been sent to prison for a long stretch, for a crime unassociated with Carlos, and the replacement he has found is only 13 and still very unpredictable.
When we meet Carlos he has just encountered a second problem. This is in the form of an envelope which has arrived at the tanning studio containing £10,000 and a contract for his next kill. The problem is that the person whose death he is meant to arrange is that of his mother. Very few people know Valerie Anderson is Carlos Morales' mother, and even fewer would address the note in the envelope to "Charlie". Only two come to Carlos's mind. One is his mother herself, and the second is his young wife and the mother of his daughter. And when he takes into account his belief that his mother has no idea what he does for a living, while his wife certainly does, the possible origins for the envelope appear to narrow further.
But how can Carlos find out for sure who sent the envelope? Talking to his wife and to his mother don't really help him get any closer to the truth, so he comes up with a scheme to flush out what is really going on. The plan we see him put into effect is convoluted, and the reader quickly gets the idea that things may not go entirely as Carlos has expected. We are also, however, kept guessing as the story mounts to a conclusion that is as complex as it is unexpected and violent.