Bloody Roses — Daphne Wright

Bloody Roses carries on the delightful adventures of Willow King, part-time dowdy civil servant, part-time glamorous romance novelist, who here faces her greatest challenge yet - to save her old friend and ex-lover.
Willow's idyllic Italian holiday with Chief Inspector Tom Worth - whom she met in the course of earlier cases - is suddenly interrupted by a frantic phone call: Richard Crescent has been arrested for murder. Richard was found drenched in blood and holding the body of Sarah Allfarthing, a colleague in the corporate finance department. The police are convinced of his guilt, and he begs Willow to return to England to prove otherwise.
She does return, and faces not only danger, but the awful possibility that the police might be right about Richard. Yet she goes into battle on his behalf, donning yet another identity in defense of her desperate friend.