between ourselves, between you and me

in good hands, in safe hands

(literally) between a dog and a wolf / (by extension, idiomatic) at dusk, at twilight; gloaming / (photography) golden hour (used in same technical sense for “good photographic light at twilight”)

(literally) Between the tree and the bark / (by extension, idiomatic) In a bad situation; between a rock and a hard place

(idiomatic) to read between the lines

Alternative spelling of entre quatre yeux

(figuratively) to fall between two stools, to have a foot in both camps, to be piggy in the middle, to be caught in the middle, to be sitting on the fence

(figuratively) to be between a rock and a hard place, to be between Scylla and Charybdis, to be between the devil and the deep blue sea, to be caught in the middle, to be caught in the crossfire

with one's tail between one's legs

(literally) between the hammer and the anvil / (by extension, idiomatic) between a rock and a hard place; between the devil and the deep blue sea