(idiomatic) to read between the lines

Alternative spelling of entre quatre yeux

in good hands, in safe hands

(figuratively) to talk under one's breath, to mutter, to mumble

(figuratively) to have a foot in both camps, to run with the hare and hunt with the hounds, to be sitting on the fence

between ourselves, between you and me

(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

(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