Sideshow: Zac and Michelle's summer thing is kaput

Um, well, they seemed to be going out . . . maybe it was just a spit-swappin' summer fling. Whatever it was or wasn't, the much-Instagrammed affectionfest between Michelle Rodriguez (of the Fast and Furious flicks) and Zac Efron, of Neighbors and every girl's dreams, this liaison so prominent in the tongue-wagging pages, is over.

An Anonymous Insider somewhat acidly tells People that the break was "very mutual." Michelle had been linked with model Cara Delevingne, and Zac had split atomically up with Vanessa Hudgens in 2010.

It's a tumultuous time for Elizabeth Vargas. The ABC News reporter, who in November revealed a lifetime struggle with alcoholism, on Sunday checked into rehab for a second time in less than a year. Now People mag says she's also filing for divorce from singer-songwriter hub Marc Cohn after a dozen years and two sons, Zachary, 11, and Samuel, 8.

 Vargas, 51, explained her return to rehab over the weekend. "As so many other recovering alcoholics know, overcoming the disease can be a long and incredibly difficult process," she said. "I feel I have let myself, my coworkers and most importantly my family down." ABC says the network supports her all the way.

Robin Williams' longtime friend and Fathers' Day costar Billy Crystal will lead an Emmy tribute to the genius comic, who died Aug. 11 of an apparent suicide by hanging.

"We felt we needed to do something powerful and memorable. Billy seemed like the perfect choice," Emmy producer Don Mischer said Wednesday.

Hosted by  Seth Meyers, the Emmys will air live Monday on ABC.

Child actress turned massive hitmaker Ariana Grande, whose "Problem" single has singed the charts, will be the opening performer at MTV's Video Music Awards Sunday. She'll perform "Bang Bang" with the hit song's cocreators, Jessie J and Nicki Minaj.

Grande says she was thrilled that her new LP, which will be out Monday, had generated such massively big hit singles.

It's been "more like a heart attack," she tells Access Hollywood. "Because it's overwhelming, it's very exciting, I'm very, very grateful - it's not what I expected."

"When I first heard the news, I was absolutely enraged," Jackie Chan posted Wednesday on his website in reaction to his son Jaycee Chan's arrest for possession of 100 grams of marijuana.

"As a public figure, I feel very ashamed; as his dad, I'm very sad and disappointed," writes the Kung Fu legend, who was an antidrug ambassador for China in 2009.

Jaycee, 31, faces up to three years in prison.

"You've done something wrong and you have to be responsible for the consequences," his father said, addressing him. "I'm your dad and I'll always be with you. We will face the road ahead of us together."

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