expression, ichidan verb
get one's stories straight; arrange beforehand to tell the same story
Used when people coordinate their accounts in advance to avoid contradictions, often in a conspiratorial or deceptive context.
彼らは口裏を合わせて、同じ言い訳をした。
They got their stories straight and gave the same excuse.
事前に口裏を
If we don't get our stories straight beforehand, we'll slip up.