Bronx Councilman Andy King has introduced a bill that could upset Elmo's world, bring Spider-Man down to Earth, and force Goofy to get his act together.

King wants to tame the posse of masked buskers who wander through Times Square, posing for pictures with tourists, asking for tips in return, and sometimes making nasty threats when a gratuity looks a little light.

The measure would require street performers who cover their faces to get a license from the city and wear it outside their costumes. This would make it tougher for masked rogues to anonymously shake down families and hide in clusters of identically dressed performers. The bill would also require these performers to be fingerprinted for background checks. Such controls are imperative:

Our streets should be exciting but not creepy.Times Square has long had the feel of a chaotic carnival. But masked cartoon characters who strong-arm adults and scare small children are a public menace. Street actors have no right to harass or threaten anyone. Visitors have every right to refuse their pleas for tips and move on.

Tourism is a mainstay of the city's economy. Last year New York hosted a record 54 million visitors, most of whom found their way to Times Square. Their presence here fuels about $59 billion in overall economic activity. But if tourists feel like targets for grifters, we can expect those carefully cultivated numbers to fall.

A license with a photo ID would let the NYPD track down masked performers who harass people and -- if the situation warrants -- charge them with crimes.

Shakedowns aren't the worst infractions some masked performers have committed. Over the summer, the NYPD arrested one character on charges of lewd behavior and collared another after he allegedly slugged a cop.

The city can't legally inhibit artistic expression. But it can regulate the way that expression unfolds in public.

Expression that violates the rights of others in Times Square should be off limits. The council must crack down on errant Elmos firmly and fast.