The Cold Light of Mourning by Elizabeth J. Duncan

Londoner Meg Wynne is about to marry wealthy Emyr Gruffydd when she disappears after getting a manicure from Penny Brannigan, owner of Happy Hands Nail Care. Penny is stunned to discover that she was the last person to see Meg, according to DCI Gareth Davies and DS Bethan Morgan. With her new friend, Victoria, Penny delves into Meg's and Emyr's lives to find out what happened to her. In her personal life, Penny starts dating Davies and mourns the loss of her good friend, Emma, who passed away recently. The Cold Light of Mourning is the first book in the Penny Brannigan mystery series and is an enjoyable cozy with a nice sense of place for small-town Wales.