Donald's Death — Gillian Larkin

What would you do if you knew someone was going to be murdered soon? Would you help them, even if you didn't know who the murderer was? Cara Daniels finds herself in this position.
In this first book, Cara discovers that her gran has to save Donald Ackroyd from being murdered within the next 24 hours. And if that isn't enough of a shock, Cara also discovers Gran is being assisted by an angel called Edward.
Gran asks Cara to help her save Donald's life. Cara agrees to do so. It's not long before Cara discovers Gran's ulterior motive for requesting her help.