While investigating the murder of a music industry executive, Mac is puzzled by the account of the victim's sister, who passes a lie detector test and swears that she and her sibling were attacked by a woman who broke into their home. However, the sister had a motive to kill her own brother, given his lucrative life insurance policy. Meanwhile, Danny and Det. Angell investigate the death of a beautiful woman found dead in a stranger's bathtub. Also, Stella has a medical scare while investigating a crime scene.