神不知鬼不觉 shén bù zhī guǐ bù jué

DEFINITIONS

  1. top secret
  2. hush-hush

CHARACTERS

神 shén spirit, god, supernatural being
不 bù no, not; un-; negative prefix
知 zhī know, perceive, comprehend
鬼 guǐ ghost; spirit of dead; devil
不 bù no, not; un-; negative prefix
觉 jué to wake up from sleep; conscious