I just finished reading Beware the East Wind by Barbara Barrett. This book is the fourth in the Mah Jongg Mystery series.
Attending a benefit is par for the course for Syd and her friends, even when the String Quartet is replaced by a hypnotist. Everyone is shocked when, a few days later the hypnotist is found dead. While they don’t know the woman, a classmate of Marianne does. Guy’s sister was the murdered woman’s business partner. Having heard of Marianne and her friend’s success at solving murders, Guy entreats her to help prove his sister’s innocence, or at least find some other suspects. Although their last case nearly proved too dangerous, the excitement of being involved in another investigation proves too heady for the four to dismiss.