Just two weeks to go before the Cherringham Charity Christmas Concert. Choir rehearsals are in full swing. Then the worst thing happens: Kirsty Kimball, one of the singers, is found dead from a severe allergic reaction to one of the home-made rehearsal cakes. Jack is pulled in to help bolster the depleted choir - and soon he's convinced that Kirsty's death was no accident. Sarah agrees, and the two of them are soon immersed in the jealousies, rivalries,...