What three letters will scare away a burglar?

A simple handwritten note is making the rounds online with a deceptively short question: “What three letters will scare away a burglar?” At first glance, it sounds like it might be about a code, an alarm system, or even a warning sign.

But the trick is in how you say the letters out loud.

The Riddle on the Paper

The image shows the prompt written in big blue marker:

“Riddle Time! What three letters will scare away a burglar?”

Most people start thinking of abbreviations like “FBI” or “SOS.” That’s exactly what makes it a fun brain teaser—your brain searches for something official or intimidating.

The Wordplay That Solves It

The answer isn’t a typical acronym. It’s a sound-alike.

When you read I C U out loud, it becomes “I see you!”—something a thief definitely wouldn’t want to hear.

The Correct Answer

Answer: I C U
Meaning: “I see you!”

That’s the whole punchline: the “three letters” are scary because they imply the burglar has been spotted.