I'll call you back
I’ll call you back means I’d rather be dead than talk to you anymore.
You’ve been on the phone for an hour about your ex’s new haircut. I’ll call you back. (You’re still on the phone.)
Your friend called to tell me about her zit. I’ll call you back. (You’re now the zit.)
You’re still talking about your pet goldfish. I’ll call you back. (You’re now the goldfish.)
xs