Kiefer Sutherland is once again losing his battle with the bottle — friends say the star of TV’s “24” is out of control, getting wasted many nights and even showing up hungover on the set.

“He’s out at bars several nights a week and he’s pulling all-night benders — showing up on the set bleary-eyed, unshaven and woozy,” an insider disclosed.

“Everyone is scared that Kiefer’s going to blow his role as the lead on ’24’ because of his wildman ways.”

Kiefer’s problems with alcohol are well documented. He was sentenced to 36 months probation for a DUI in 1992 and he’s been involved in several drunken barroom brawls.

And for the past month or so, he’s been partying at his favorite bar, Candy Canyon, near the “24” production office in Woodland Hills, the insider revealed.

“Kiefer stays there all night drinking and when they finally boot him out, he goes to the ’24’ set and sleeps in his trailer,” said a source close to the 35-year-old star.

“He reeks of alcohol. It’s got his co-workers worried sick.”

An ENQUIRER reporter watched Kiefer at Candy Canyon on Wednesday, October 23, and saw the actor down eight shots of J&B scotch, take off his shirt and gyrate topless — and even lap dance on a guy’s knee!

Kiefer was in the company of eight men, mostly burly and all wearing baseball caps, and one dark-haired girl in her mid-20s.

By 11 p.m., he’d already downed at least four shots of scotch. And he just kept ordering them. At one point the barmaid came around the bar with a bottle of J&B and filled his glass from it.

Kiefer sat next to a girl and she gave him back rubs. Several times they got up and danced cheek to cheek as a customer sang karaoke.

Kiefer also had several dances with a gorgeous blonde barmaid who was off-duty that night and joined the group.

As the evening wore on, Kiefer took off his white T-shirt, flung it around his head a few times and did a lap dance on one of his male buddy’s knees before falling to the floor.

When last call came at 1:30 a.m., Kiefer got up and did the last karaoke number of the night, the Dylan classic “Knockin’ on Heaven’s Door.”

The bar crowd roared and cheered when he finished.

At 2 a.m., when everyone was leaving, Kiefer paid the tab for his whole group.

Outside, two photographers tried to take his picture but his buddies surrounded them and threatened violence.

Said photographer Joe Phetsomphou: “Kiefer was drunk, very drunk. He said: ‘O.K., you guys caught me. I’m wasted.’

“We were afraid his buddies were going to smash our cameras or punch or kick us. But Kiefer walked up smiling and said: ‘You want pictures? Take all the pictures you want.’

“So he posed with a couple of his buddies and we snapped away.”

The ENQUIRER reporter saw Kiefer get into the driver’s seat of his black Range Rover and the girl he was with get in beside him. For the next 50 minutes they argued over who would drive.

Kiefer drove about 40 yards, then stopped. Then he drove another 10 yards, stopped and the pair bickered some more. Then they repeated the process across the parking lot.

Finally he switched off the engine and they both got out. He got into her car and she drove.

Said the close source: “Kiefer has hit a lot of peaks and valleys in his drinking life. He even had to pay $14,000 to a man he head-butted in a Vienna bar.

“He cleaned up his act briefly in October 2000 in an attempt to win back his wife Kelly Winn. But the reconciliation didn’t work out and he dove back into the bottle.”

A friend who saw the actor at a recent party in the Hollywood Hills said: “Kiefer walked in late with a bottle of J&B scotch in his hand. No glass — he was drinking right from the bottle.

“He was completely blotto. He wasn’t obnoxious or nasty, just obviously drunk out of his mind.

“Everyone’s hoping he gets a grip on his boozing before something bad happens.”