Unable to sleep

AWAKE

The opposite of what you’d call someone in a deep slumber at midnight.

"Unable to sleep" is a straightforward definition clue pointing to a state of being conscious when you’d rather be resting. The answer "AWAKE" fits perfectly because it directly describes someone who isn’t asleep. There’s no hidden wordplay here—just a simple, literal connection between the clue and the answer. If you’ve ever tossed and turned at night, you’ve been in this exact state.