mystery

• Vanish into thin air

  To disappear completely and suddenly without leaving any trace or explanation.

• Into thin air

  To disappear completely and mysteriously without leaving any trace.

• Curse of the pharaohs

  The belief that disturbing ancient Egyptian mummies or tombs will bring misfortune, illness, or death upon those involved.

• Cloak and dagger

  This phrase refers to activities or situations characterized by secrecy, intrigue, espionage, and often danger.

• A closed book

  Someone or something that is difficult to understand, particularly a person whose thoughts or feelings are not easily known.

• An enigma

  Someone or something that is mysterious, puzzling, or difficult to understand.

• An unseen presence

  A perceived but invisible entity or force, often associated with a sense of mystery, apprehension, or the supernatural.

• Enigmatic

  Puzzling, mysterious, or difficult to comprehend.

• There's more to it than meets the eye

  The true nature or full extent of a situation, person, or object is not immediately obvious and suggests a deeper, often hidden, complexity.

• There's more than meets the eye

  Something is more complex, interesting, or significant than it initially seems.