Disguise

Many cases and arcs involve the use of a disguise.

Characters who specialize in disguise

Many of the characters who specialize in disguise studied on a magician, and many magicians in Detective Conan also have disguise abilities.

Vermouth

Chris revealing her true identity.

Yukiko Kudo

Yukiko in her normal disguise form.

Detective Conan vs. real world disguise

In real world, creating a facial mask may be possible, but trying to impersonate other people and not to mention in a short amount of time is more likely impossible. In Detective Conan, Vermouth and Kaitou Kid seems to change themselves really quickly (and easily) unlike Yukiko who had 7 hours of time to dress Heiji and Conan.