What’s the catch?

What's the catch?

What's the problem, drawback, detriment, or risk that I'm not privy to or able to see? A: "He said he'd lend me $20,000 to buy a new car, then I'd just pay him back whenever I'm able." B: "Whoa. What's the catch?" Why are you selling this for so little? What's the catch?

What’s the catch?

interrog. What is the drawback?; It sounds good. Are there any hidden problems? Sounds too good to be true. What’s the catch?