Sudden Mischief by Robert B. Parker

In this gripping detective novel, private investigator Spenser is drawn into a complex web of deceit and danger when his girlfriend Susan Silverman's ex-husband, Brad Sterling, seeks his help. Sterling, a charming yet dubious character, is embroiled in a scandal involving accusations of sexual harassment and financial misconduct. As Spenser delves deeper into the case, he uncovers a trail of secrets and lies that lead to a powerful and ruthless adversary. With his trademark wit and unwavering moral compass, Spenser navigates the murky waters of betrayal and corruption, determined to uncover the truth and protect those he cares about.