Doe is a sympathetic character with a gritty sexiness, a bit of wry humor, and a MacGyver-like ability to get himself out of any scrape. His capacity for acquiring knowledge is impressive -- which helps when he needs to escape handcuffs or pilot a helicopter.
Since John Doe is a crime show, it's not surprising episodes involve murder, guns, and violence. In one episode, for example, a rogue ex-cop and his crew take the police station hostage, threatening groups of people with automatic weapons and at one point opening fire and wounding someone. In another scene, the ex-cop strikes his former boss, Jamie Avery (Jayne Brook of Chicago Hope and Boston Legal), across the face, knocking her to the ground. Other episodes include some brutal killings, serial murderers, and even a swimming pool filled with blood. It's not as graphic as CSI, but it's definitely not for little kids.