Nurse!

Jake Gyllenhaal socked a mirror on the L.A. set of his new movie -- slicing up his hand so badly, he was rushed to the hospital to be stitched up.

It all went down Wednesday morning, according to People.com ... Jake "flipped out" during a scene for "Nightcrawler" and punched the mirror with his fist, shattering it and damaging his hand in the process.

Jake was reportedly taken to a nearby ER where he was treated and released. He returned to the set later that day.

Zac Efron broke his jaw and gashed his face in what people say was a violent fall in his house after slipping in a puddle of water ... yet there was NO 911 call.

TMZ checked with law enforcement sources and no one called 911 to report any incident on Sunday -- when the injury occurred. We checked the days prior to and after Sunday as well -- No 911 call.

The mishap is puzzling for sure. Zac has been in rehab twice this year for cocaine abuse. He's also had problems with Molly and we're told staying sober has been a struggle.

It's unclear how Zac made his way to the ER ... but given that the injury was so severe his mouth had to be wired shut ... it's bizarre it didn't warrant a 911 emergency.

Zac Efron broke his jaw. His jaw is wired shut. It supposedly happened when he slipped in a puddle of water at his home. That's Zac's story.

Zac has been in rehab twice this year for cocaine abuse. He also had been dabbling in Molly.

In addition to the broken jaw, Zac apparently also suffered a big ol' gash that had to be closed with stitches.

Maybe it's true, but it's a very weird story ... slipping and breaking your jaw in a puddle of water.

We're told Zac -- who has been a hard partier for years -- has been struggling to stay clean.

"Amish Mafia" star Esther Schmucker has come out of hiding -- revealing her bruised and battered face in public for the first time since her boyfriend allegedly used it as a punching bag.

Schmucker was sporting a seriously black eye as she went out on a shopping run ... but she didn't have much to say, telling a photographer, "I don't feel like talking to anybody."

As we reported ... the beatdown left Schmucker with a broken nose and cheekbone ... and several broken teeth. She hasn't been seen in public since her boyfriend -- Imir R. Williams -- was arrested for the Oct. 31 attack on her face.

Justin Bieber must have eaten some bad empanadas in Argentina ... 'cause the singer just revealed he's got food poisoning.

Biebs dropped the crappy news on Twitter Sunday evening, but quickly assured fans his sour gut would not result in any canceled concerts ... at all.

It's one more piece of bummer news for Justin whose current Central and South American tour has been plagued with issues -- like destructive fans, fake hookers, graffiti tickets and hotel problems.

Good thing Pepto-Bismol is global.

The guy who played Jim McCoy on the hit History Channel mini-series "Hatfields & McCoys" claims he was bucked off a horse on the set and suffered serious injuries back in 2011 -- and now he's suing, TMZ has learned.

Thomas McKay -- who also stars in "The White Queen" on Starz -- has filed a lawsuit against the producers of "H&M" claiming they lied to his face when they told him he was in good hands with the on-set horse experts.

According to the suit, filed in L.A. County Superior Court, Thomas claims the handlers were not only incompetent -- but they put him on a horse that was ill and out of control.

The result -- Thomas claims his horse became uncontrollable during the filming of a scene, bolted, and "subsequently threw [him] into a tree."

McKay claims he suffered serious and permanent injuries -- which caused "great physical, mental and nervous pain." The exact injuries were not disclosed.

McKay also claims the horses were abused on the set -- which was in Romania.

The 33-year-old actor is suing Hatfield & McCoys Productions, Thinkfactory Media and others for unspecified damages.

The L.A. County Dept. of Children and Family Services has opened a fresh investigation into allegations that someone hurt Bob, one of Charlie Sheen and Brooke Mueller's twins ... and we've learned Brooke is pointing the finger at Denise Richards.

Sources familiar with the situation tell TMZ ... Brooke reported the incident over the weekend, just after Charlie appeared on TMZ Live and railed on her. We've learned Brooke told DCFS ... there was a cut on Bob's back that was deep enough to scab over, and she said it happened on Denise's watch.

As you know ... Denise was the guardian of the twins while Brooke tried to beat her latest bout of drug abuse. Denise threw in the towel yesterday, saying the kids were too violent, and now Brooke's brother Scott is the guardian.

We're told social workers went to Bob's school and determined the cut had been there for more than a week, which means it could have happened while Bob was under Brooke's care. DCFS then interviewed Denise, who said the cut had been there for more than a week.

Our DCFS sources say the timing of Brooke's complaint is suspect because the accusation came on the heels of Charlie attacking her on TMZ Live.

Adrienne Maloof was injured a few minutes ago while shooting a segment for an entertainment show on the CBS lot in the San Fernando Valley.

Sources say a light got too hot and popped over Adrienne while she was filming an interview with her boyfriend Jacob Busch. One eyewitness says the former "Real Housewives of Beverly Hills" star fell and hurt her knee.

We're told it sounded like an explosion, which startled her. Everyone around could hear glass breaking. Adrienne actually started to run away when she fell.

A fan and close friend of Blink 182 was rushed to an L.A. hospital last night during the band's sold-out concert at the Hollywood Palladium -- after falling from a 2nd-story balcony inside the building, Blink's rep tells TMZ.

Witnesses described the mayhem on Twitter, saying the fan fell "face first" while Blink was playing "Dammit" and looked in rough shape after the accident. The fall was roughly 15-20 feet, but witnesses say he was responsive.

One witness who was standing under the balcony tells TMZ, the man landed right next to her and his body made the "gnarliest splat on the ground ... I can still hear the sound. It was awful." He didn't land on anyone. The witness says he had blood all over his face.

According to the rep, the fan is a "dear friend" of the band, but the rep wouldn't be more specific.

It's unclear how the fan fell, and whether his injuries are life-threatening. He's currently being treated at a local hospital. The rep says the band is in touch with the man's family.

Janice Dickinson got blasted in the head by a closing parking garage gate, allegedly, and now she's suing Rite Aid over her injuries ... TMZ has learned.

In her legal docs ... Janice says she was on Canon Drive in Bev Hills back in July ... when she was smashed in the cabeza by the steel barrier of the parking lot adjacent to Rite Aid.

She is claiming the drug store giant was negligent by failing to "adequately inspect, maintain and/or control the premises."

Translation: bad upkeep on their equipment made Janice fall and go boom.

In the lawsuit, Janice isn't specific, but says she suffered serious physical and emotional injuries. As TMZ first reported ... Janice says doctors at UCLA medical center checked her out after the accident and told her she had a nasty concussion.

Denise Richards was armed with an email when she went to the L.A. County Dept. of Children and Family Services -- an email which she apparently believed would expose Brooke Mueller as a terrible parent.

The email -- obtained by TMZ -- was sent by Dr. Jay Gordon, an Assistant Professor of Pediatrics at UCLA Medical School. The email and documents obtained by TMZ make it clear ... Brooke is blocking psychological treatment for Bob and Max.

The email, dated August 23, 2013, reads:

-- "As we have discussed, because of recent events involving the boys' behavior I think that they need urgent evaluation. I am very concerned about their escalating violent actions; The apparent lack of understanding of the consequences and the safety of others is most worrisome. I would like them seen by Dr. Alessia Gottlieb for a complete developmental and behavioral assessment."

Olympic gold medalist Ryan Lochte has been forced into a break from his swim training ... after tearing up his knee in a bizarre accident -- on dry land.

Lochte's rep tells us ... The 11-time medalist tore his MCL and sprained the ACL in his left knee ... when he greeted an overly excited fan in Florida who ran and plowed into him.

The teenage girl knocked Lochte to the ground ... and smacked his knee on a curb causing the severe injuries.

Team Lochte says Ryan will take an immediate break from training and competition. But we're told his medical team expects a full recovery.

All is not lost, Team USA.

TMZ obtained these pics from sources connected with the L.A. County Dept. of Children and Family Services ... and they purportedly show 4-year-old Bob Sheen before and after a visit with Brooke Mueller ... we've learned Charlie Sheen believes it's proof she's NOT a fit parent.

DCFS sources tell TMZ, Denise Richards -- who has temporary guardianship of twins Bob and Max -- included the before/after shots in her letter to DCFS, claiming a photo was taken just before Bob was dropped off at Brooke's place on July 26 ... and the other taken after leaving Brooke's care.

Denise didn't say what the red mark was, but we're told Charlie believes it was a burn.

It appears Brooke told DCFS Bob's face was already red when Denise dropped him off.

As we reported, according to our DCFS sources ... Denise recently wrote the letter to DCFS in order to say she could no longer care for Charlie and Brooke's twins because they have become out of control and violent, hurting her animals and her daughters.

"Amish Mafia" star Esther Schmucker was allegedly beaten to a pulp by her boyfriend last week in Pennsylvania -- suffering a facial fracture, broken nose, and more -- and now police are trying to track the man down.

According to reports, cops in Strasburg, PA issued a felony arrest warrant for 24-year-old Imir R. Williams on Sunday. Williams has been charged with felony aggravated assault in connection with the alleged beating.

Police claim Williams attacked 27-year-old Schmucker early Halloween morning, repeatedly punching her in the head.

In addition to the face fracture and broken nose, police claim Schmucker suffered broken cheekbones and several broken teeth.

As of this morning, police were still searching for Williams, who's described as 6'4" and 210 pounds. Authorities believe he's either in Lancaster or New Jersey.