| Detective | Gardner | The detective-in-charge on Cody's case. |
| Dr. | Griffith | Dr. Hale's colleague. |
| Adrienne | Hale | A psychologist. Disappeared. AKA: Dr. Hale. |
| Mr. | Harris | One of Dr. Hale's patients. |
| Lola | Hernandez | One of Dr. Hale's patients. |
| Mrs. | Lawton | Patricia's mother. |
| Stanley | Milgram | A famous Yale psychologist. |
| Luke | Strauss | A clinic technician. Dr. Hale's boyfriend. |
| Judy | Teitelbaum | Ethan and Tricia's real estate agent. |
| Whitney | Young | The first person that Tricia killed. |
| Alexis | | Megan's boyfriend. |
| Bertha | | Tricia's great-aunt. |
| Bob | | Tricia's uncle. |
| Cody | | P.J.'s fiancé. |
| Darcy | | Luke's ex-wife. |
| Debbie | | Tricia's aunt. |
| Delilah | | Ethan and Tricia's daughter. |
| E.J | | Dr. Hale's narcissistic patient. AKA: Edward Jamison. |
| Ethan | | Tricia's husband. |
| G.W | | One of Dr. Hale's patients. Ethan's mother. AKA: Gail Wiley. |
| Gloria | | The receptionist. |
| Megan | | P.J.'s best friend. |
| P.L | | One of Dr. Hale's patients. AKA: Patricia Lawton. |
| Paige | | Dr. Hale's agent. |
| Susan | | E.J.'s mother. |
| Tricia | | Ethan's wife. New owner of Dr. Hale's house. |