get (one) off the hook
To free one from the responsibility of having to complete some task; to help one to avoid something. Thank you for getting me off the hook for Saturday—I was dreading having to babysit at 6 AM on my day off! Can you please tell mom that you broke the vase and get me off the hook?
get somebody off the ˈhook
(informal) help somebody to avoid punishment, etc: You’re going to need a very clever lawyer to get you off the hook.