Theme: Amnesia

Amnesia is the partial or complete loss of a person’s memory. This is an acknowledge medical condition in the real world. It is a common trope in fiction where a person wakes up with no memory and spends the story discovering who they were.

This trope regularly appears in genre stories where the protagonist must discover who (or in some cases what) they are. There are quite a number of stories where characters wake in an alien environment with no memory.

Also common in genre material are stories about amnesia-inducing drugs or operations. Or else of people whose memories have been wiped for a particular purpose.

See also Altered Memory dealing with amnesia inducement and artificial memories.