When Devlin arrives late for the birth of Eloise O'Connor, he can't believe his best friend has taken over his position as her guardian angel. Though Devlin pleads with Nathaniel to hand the child's guardianship back over to him, he refuses. The two angels have been friends for thousands of years, but after seeing how tiny and vulnerable the baby is after a difficult birth, Nathaniel isn't willing to risk her life with a tardy, irresponsible angel. Devlin's new obsession with fallen angels and sexy women seem to be affecting his judgment and Nathaniel believes he's planning to sell his soul, which would put Eloise in even more danger. Outraged, Devlin accuses Nathaniel of betrayal and threatens to guard Eloise, with or without his approval. After eighteen lonely years of missing his best friend, Nathaniel hopes his Devlin will come to his senses and visit him, but the day Devlin turns up, the battle of the two angel begins.