be in deep waters —(also: be in deep water) be in trouble or serious financial difficulties:
- Spence inspected the books and realised the mining company was in deep waters with the falling copper prices.
Note: The expression does not correlate in meaning with the phrase be too deep for someone—be too difficult or complicated for a person to understand or deal with successfully:
- Perhaps the subject is too deep for me. Or the statements of the ancients too obscure and incoherent…
do a deep dive—explore an issue or subject in-depth:
- I felt that this book did a deep dive on many topics that other books just briefly introduced.