| 1 | Charlie |
| Jason's son. |
| | Daniela |
| Jason's wife. A painter. aka: Dani Varcas. |
| | Ryan |
Holder | Jason's college buddy. A neuroscientist. Won the Pavia Prize. |
| | Jason Ashley |
Dessen | Narrator. Protagonist. Atomic Physicist. A teacher. |
| | |
| The EL - A dark place, street. |
| 2 | Leighton |
Vance | Chief Executive and Medical Officer. Jason's colleague and friend. |
| | Amanda |
Lucas | Jason's therapist. A psychiatrist. |
| | Chad |
Hodge | An employee at Velocity Laboratories. |
| 3 | Randolph |
| Attending physician at Mercy Hospital. |
| | Barbara |
| Nurse. |
| 5 | Juliane |
Springer | Randolph's colleague. |
| | Ralph |
| The guy who picked up when Jason tried dialing his wife's number. |
| | Randall |
Dessen | Jason's father. |
| | Ellie |
Dessen | Jason's mother. |
| | Michael |
Dessen | Jason's brother. |
| | Steve |
Konkoly | Producer. |
| 8 | Matthew |
Snell | The first guy who used the box. |
| 10 | Nadia |
| The girl who was with Mike. |
| | Mike |
| The driver who helped Jason out. |
| 13 | Gary |
| The man who was working at the gun shop. |
| | Nick |
| Restaurant Manager. |
| | Officer |
Hammond | Police officer. |
| 14 | Joel |
| Charlie's friend. |
| | Angela |
| Charlie's girlfriend. |