red-handed vs unprepared

red-handed

adj
  • Deadly, bloody. 

  • Showing clear evidence of guilt; in the act of wrongdoing. 

  • With hands that are red from blood. 

unprepared

adj
  • Not prepared; caught by surprise. 

noun
  • A black mark given to a pupil who arrives at a lesson without the necessary items or preparation. 

How often have the words red-handed and unprepared occurred in a corpus of books? (source: Google Ngram Viewer )