Exclusives

Law enforcement sources tell TMZ Chris Brown is being investigated by the LAPD in an alleged assault on a female.

According to police, Brown and a woman whom cops refuse to identify were arguing inside a vehicle around 12:30 this morning when suddenly things allegedly turned violent.

Cops say they received a 911 call, and when they arrived they noticed the woman had visible injuries. We're told she then identified Brown as her attacker. Cops say Brown had left the scene by the time police arrived.

Cops say they are looking to speak with Brown and may arrest him when they find him.

When we called reps for Brown's girlfriend, Rihanna, for a statement, her people told us, "Rihanna is well. Thank you for your concern and support."

UPDATE: Grammy officials have just announced that Rihanna will neither perform on the show tonight -- as scheduled -- nor walk the red carpet for the event. The same announcement has been made about Chris.

The former "Celebrity Rehab" star was in court today where the judge ordered him to check himself into Cri-Help Treatment Center first thing Monday morning.

Adler was popped last week for failing to complete court-ordered community service by the judge's deadline -- that punishment stems from a prior DUI bust.

Jessica Simpson is already explaining her reportedly bizarre, calamity-filled, lyric-forgetting performance in Michigan last night -- chalking the whole thing up to an "off night."

Her rep tells TMZ, "Jessica had an off night. She's a perfectionist and wanted to start some songs over. She always wants to give the best performance for her fans."

Jess' recent wave of bad press continued this morning when a Grand Rapids Press editor who attended the show claimed the singer forgot her lyrics, struggled with her ear monitors, mumbled through songs, fought back tears and asked her band to re-start a song.

At one point in the show, Simpson mouthed the words "I'm sorry" to the crowd.

FYI -- no apology has been issued for the years of the other shows she's done.

One of the members of the legendary hip hop group, Krayzie Bone, told us he's in talks with K-Fed and will give him a try-out of sorts: "We will listen to his music and if it's jumpin' off ... if we can do business ... Bone is all about doin' business." In fairness to Bone, the guy admits he's never listened to K-Fed's old stuff...

But Bone says he's not concerned about taking a risk on someone who's been described as the laughing stock of rap because, "We feel like we can work with anybody and have a platinum hit ... our fan base are usually the ones who respect a man who has gone through a lot of s**t."

David Martz tells us he was flying Tommy Lee back from Palm Springs when he saw a house fire over the Glendale area. He says he noticed an LAPD chopper about 800 feet over him but it was no big deal.

Martz says when he landed, he and Tommy celebrated with a bottle of Grey Goose vodka mixed with lemonade -- a bottle they carried in Tommy's luggage.

Martz says the cops arrived 15 minutes after he landed and accused him of flying under the influence. They gave him a field sobriety test which Martz claims anyone would flunk -- alleging the whole "toe-to-toe" maneuver was impossible, and one time he accidentally picked his nose when he was supposed to touch it.

Martz claims the cops were hostile and took him to the station, where he blew a .01 and .02. When they finally released him, he didn't have a ride so the cops took him to Tommy Lee's pad -- and let him take his Grey Goose along for the ride.

Toni Collette's performance in "The United States of Tara" didn't exactly bring the house down -- but it may have caused a roof to collapse.

The owner of a BBQ joint in the San Fernando Valley is suing the makers of the Showtime show, claiming a day's worth of filming in his restaurant left nearly $400K worth of damages.

According to the court docs, the owner of the joint, Un Suk Yun (common spelling), agreed to rent out his restaurant for one day last September. But, Yun claims, "due to many heavy movie machine's pressure, the roof and ceiling came down" -- causing serious damage and forcing him to shut down the eatery for two weeks.

Not Daniel Radcliffe -- dude kept his magical trap shut in New York yesterday -- both times -- when we asked how stuntman David Holmes was doing.

FYI -- Holmes -- who was injured during an aerial stunt for the upcoming Harry Potter movie -- has just been transferred to a medical specialist in London who could further examine the damage to his back and legs.

Former MLB star Lenny Dykstra earned the nickname "Nails" for his tough and aggressive playing style. But four men have a new nickname for him: Deadbeat.

According to a lawsuit filed today in Los Angeles Superior Court, Dykstra has yet to fork over the cash he promised to pay four pilots in exchange for flying his private plane. Dykstra had until January 12 to pay up, the lawsuit says, but thus far he hasn't.

What's more, the four pilots claim Dykstra promised them a four-month gig, but didn't deliver on that either.

UPDATE: 10:25 PM ET: Bynes' lawyer, David Feldman, said it was a minor fender bender where cars were traveling 3 - 5 mph -- bumper were touched and that's it. Feldman went on to say there were no injuries or damage to the cars. And Feldman says the plaintiff filed the lawsuit one day before she would have been barred forever from suing and not once did she ever notify Bynes that she suffered any injuries.

Some celebrities have a problem with drinking and driving. Amanda Bynes just has a problem with driving.

Bynes has been involved in two car accidents in the last two years, and now she's being sued over one of them.

It was a multiple car collision at a very busy intersection in Bev Hills. We're told it was a chain rear-ender with four cars involved.

Bynes is being sued for hospital bills and damages. The plaintiff, Shari Landon, is suing two other drivers, along with Hertz.

The man who is building the house that caused Ashton Kutcher to melt down says the actor is acting "silly."

Bruce Goldsmith, a screenwriter, says he's "startled" that Kutcher went crazy this morning at 7:30 AM, complaining of noise at

.

Goldsmith was quick to point out the city of L.A. allows him to start construction at 7:00 AM, and that Ashton "just doesn't want to deal with reality." Goldsmith says Ashton, who called him a "dickweed," a "jackass" and "owl feces cougar placenta," is "out of line." As Goldsmith says, "they don't make hammers covered with rubber."

Goldsmith finds it somewhat ironic that the house Kutcher lives in was built over a ten year period and neighbors had to deal with the noise.

He adds Kutcher has been pleasant in the past but has complained, with Goldsmith telling him he "can't do anything about the noise." He's been building the house for six months.

Our cameraman was waiting for Jake to return from a scheduled lunch break from jury duty, when a frustrated Gyllenhaal walked into the door after pushing instead of pulling. We asked how he was doing ... wrong question ... Jake stomped down into our guy's shin.

Jake's now inside the courthouse, waiting to find out if he'll be selected on a jury that will hear -- get this -- a battery case.

UPDATE: 5:14 PM ET: Gyllenhaal was just excused from jury service in the battery case ... probably because he just committed one!

A dude claims he's the inspiration and more for "Hannah Montana" and wants Disney to give him due credit -- as in a lot of money.

Richard Fronduto filed a lawsuit today in L.A. County Superior Court, claiming he wrote a script in 1990 called "The Secret Life of Sindi" which eventually became "The Family Business."

Fronduto claims his agent pitched his work to Disney and that Disney liked it so much they asked him to turn his script into a two-hour pilot. In short, he claims he's the brainchild for what became "Hannah Montana."

Fronduto claims numerous similarities between his script and "Montana." Both feature a 13-to-14-year-old middle class American girl who leads a double life as an ordinary teen and successful pop star. Both feature a single parent who acts as her alter ego's manager. And both have a best friend "with whom she shares her secrets." Doesn't that sound like half the Disney shows? We're just sayin' ...

John Landis has filed legal papers against Michael Jackson, claiming Jacko had no right to negotiate a deal to make a Broadway musical of "Thriller," without his consent.

Landis wrote and directed the "Thriller" video and documentary back in 1983. Reports surfaced recently that Jackson cut a deal with the Nederlander Organization wherein Jackson made a deal in excess of $400,000 for the musical. But Landis claims Jacko can't cut a deal without his consent.

Landis, through his lawyer, Miles Feldman, is asking a L.A. County Superior Court judge for a declaration that Jackson can't make the deal without his sign off.