deep blue sea
Noun
Meaning
deep blue sea (countable and uncountable, plural deep blue seas)
Sea, ocean, open sea.
Examples
Coleman 2005, p. 271. In 1955 Leigh starred in Anatole Litvak 's film The Deep Blue Sea ; co-star Kenneth More felt he had poor chemistry with Leigh during the filming.
This reminds me of that bit in the movie Deep Blue Sea where ‘Preacher’ (LL Cool J) thinks he’s going to die, and his last words to the world are how to make the perfect omelette.