Dimwits, or Idiots, are villains who rarely (if ever) use their heads. In other words, these villains are seen as dumb and simple-minded, and are very likely to foil their own plans or other villains' plans and can even cause them to ruin themselves; this is usually due to poor planning, stupidity, ineptitude, bumbling, or even slowness. Furthermore, some of these villains (such as Beavis and Butt-head) can be viewed as being Amoral, as they may not always be aware of their actions due to their stupidity. Most of these villains are also Incompetent because of their stupidity.

Not to be mistaken with characters who are Mentally Ill (such as Leatherface, Jason Voorhees, etc.), or those with genuine learning difficulties (such as The Great Child, etc) , as there is a major difference between the two categories. They are also the polar opposite of Masterminds, who are exceptionally intelligent and resourceful characters.

It is uncommon for a Pure Evil to actually be dimwitted; however in some cases their actions can prove to be too unpleasant, heinous, and cruel that even they could get themselves harmed or worse (e.g. Chaka, Hydell and Craster). Pure Evils who fall in this category tend to be particularly sadistic, impulsive, merciless, and bloodthirsty, and very often require the assistance of more intelligent (or at least more collected) villains.