at someone's beck and call

at (one's) beck and call

Completely compliant or obedient to another person; catering to one's every need. The phrase has a negative connotation. Do you really think I'll do anything you say? I'm not at your beck and call! A: "How can we get to the mall this weekend?" B: "Oh, my sister will take us—she's been at my beck and call ever since I caught her sneaking in past curfew!"
See also: and, beck, call

at someone's beck and call

Required to comply with someone's requests or commands, as in The boss expects the entire staff to be at his beck and call. The noun beck, now obsolete except in this idiom, meant "a gesture or signal of command, such as a nod or hand movement," whereas call signifies "a vocal summons." Also see dance attendance on.
See also: and, beck, call

at someone's beck and call

always having to be ready to obey someone's orders immediately.
Beck in the sense of ‘a significant gesture of command’ comes from the verb beck , a shortened form of beckon . It is now found mainly in this phrase.
See also: and, beck, call