getting through between a rock and a hard place

The Narrow Straights.

In Greek mythology, Scylla is a legendary monster who lives on one side of a narrow channel of water, opposite her counterpart Charybdis. The two sides of the strait are within an arrow’s range of each other—so close that sailors attempting to avoid Charybdis would pass dangerously close to Scylla and vice versa. Scylla is depicted as a maiden with a kētos tail and dog heads sprouting from her body. Charybdis was punished by Zeus and transformed into a monster, with flippers for arms and legs, and an uncontrollable thirst for the sea. As such, she drank the water from the sea thrice a day to quench it, which created whirlpools