They’re getting ready.

They’re pulling out that favorite pair of worn Levi’s with the hole in the butt, slipping on a tight, black t-shirt and making sure their wallets are chained to their belt loops.

Yep, Metallica is in town and with it a faithful following of “Metalheads” — enough to make any police force beef up its numbers.

There will be a few thousand extra people in Ames for tonight’s concert. And the loyal pack of head-banging fans has a reputation for partying hard. Ames police officers are preparing themselves for what could turn into an interesting evening.

Then again, officials say, it could very well be just another concert.

We’ll see.

With thousands expected to take in a night of hard-rock festivities, Iowa State Center officials have requested extra officers for the concert, for those “select few” Metallica fans who get out of hand.

“We will be providing about eight to nine additional officers at the concert as opposed to on the street, because that is where they will be needed,” said Dennis Ballantine, Ames police chief.

Iowa State Department of Public Safety officials use the performing group and concert size to judge how many extra officers they’ll need.

“Because it is a group like Metallica in concert and with possibly more than 12,000 people attending we may have a few extra officers on duty than usual,” said DPS Director Loras Jaeger.

Ballantine said most concerts have about five to seven arrests. But because rock-music crowds, especially Metallica crowds, are notorious for getting out of hand, he said those numbers may go up tonight.

Still, Ballantine is hoping the arrest numbers are lower than those from November’s Phish concert.

“After the Phish concert we ended up with more than 20 arrests. That crowd was definitely a different crowd than we are expecting [tonight]. We are in no way expecting those kinds of numbers,” he said.

Jaeger said DPS isn’t going into the evening expecting to arrest a large number, either, “but we do want to be ready in case there are any problems.”

Police will be concentrating on public intoxication and underage drinking.

However, lately a large number of Ames concert arrests have been drug-related.

“… there have been more arrests for possession of a controlled substance at these concerts,” Ballantine said.

The usual problems arise from fights started by intoxicated fans.

Jaeger, too, remains optimistic.

“Hopefully there won’t be any arrests at all. We want everyone to have a good time, and stay out of trouble. If we don’t have to arrest anyone, everyone will be happy,” he said.

Metallica kicks off at 7 p.m. in Hilton Colisium.