Crack developed rich and deep (8)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
decipher
But I can't explain it at all! Could you help me understand?
(Other definitions for decipher that I've seen before include "Break code" , "Convert from code into plain language" , "Make sense of" , "Unscramble" , "Crack" .)