The secret of Harry Houdini's (search) signature "Metamorphosis" escape trick is out of the bag.

A new exhibit, "A.K.A. Houdini," opened Wednesday at the Outagamie Museum (search), revealing how Houdini, handcuffed inside a sack and locked in a trunk, somehow managed to switch places with an assistant on the outside. (IF YOU DON'T WANT TO KNOW IT, DO NOT READ THE NEXT PARAGRAPH.)

Among other things, the trunk has a side panel that allows someone inside to sneak out.

The revelation didn't spoil a thing for museum visitor Matthew Martin, a missionary from Orem, Utah. "I think it's still impressive if someone can do it in three seconds," he said.

But the disclosure has some in the business tied up in knots.

Magicians say their code of ethics prohibits revealing secrets to the public. The famous and not-so-famous alike, including David Copperfield (search) and Ronald "Rondini" Lindberg, have called to protest its "A.K.A. Houdini" show.

"It's just that this is a very, very passionate thing that magicians feel about and what the museum is doing is wrong," Lindberg said.

Museum officials in Appleton, a city of about 70,000, insist the exhibit hasn't revealed anything not already available in books and on the Internet. They also say people will appreciate magic more by knowing the secrets.

The exhibit -- set to run for 10 years -- includes 38 artifacts, 190 documents and hands-on displays. There are a straitjacket and a jail cell from which visitors can try to escape, plus Houdini items such as handcuffs and lock picks.

The part of the exhibit showing how tricks were actually performed is in a backstage area. A sign warns visitors: "Those who do not want to know how Houdini performed his magic should avoid this area."

In the "Metamorphosis" trick, also known as the "substitution trunk," a magician, handcuffed in a sack inside a trunk, frees himself and switches places with an assistant standing by the trunk.

The exhibit lets visitors climb inside the trunk to see how it works. Houdini first performed the trick more than 100 years ago with his wife.

Kim Louagie, the museum's curator of exhibits, said before the exhibit opened that it had received more than 200 e-mails and 40 phone calls from people against the idea of revealing secrets. She said it has also received much support from museum members and others in the community.

"In some ways what we're doing here increases the value of magic rather than making it something cheap," she said.

She said there had been rumors in Internet chat rooms of plans to sabotage the exhibit, and police had been contacted to step up patrols around the area. But there was no trouble when the museum opened Wednesday morning.

Bob Rath, a professional magician and small business owner, comes down on the museum's side. It would take hours of practice to do the trick successfully, he said.

"The performance is more important than the secret, and just because somebody is going to know the secret to Metamorphosis isn't going to make them any great magician, he said. "It's a very complicated and very difficult effect to do."

The Houdini Club of Wisconsin, however, is displeased about the trick's exposure because it has bylaws that prohibit such a thing, said Rath, the club's vice president. Besides, he said, there are many magicians around the world still using it.

"There are a lot of people in the organization that are real upset," Rath said.

Houdini was born Ehrich Weiss in 1874, in Budapest, Hungary. His family moved to Appleton when he was 4, when his father became the town rabbi. They stayed for four years.

He embarked on a career in magic and later focused on escapes. He died of peritonitis resulting from a ruptured appendix in Detroit on Halloween 1926.