On his trip to Australia, Zac Efron seemed preoccupied with what was going on down under.

Cameras caught a glimpse of the A-list heartthrob on the balcony of his Sydney hotel Monday, and it was hard not to notice that the High School Musical hunk had his hand jammed down the front of his pants (for reasons we won’t even dare to speculate on).

It's two of Hollywood's hottest hunks - and a bike.

High School Musical star Zac Efron told Jimmy Fallon Wednesday he was talking about motorcycles with perennial A-lister Tom Cruise at a party, when Cruise asked him, "Hey man, do you ride?"

Cruise then asked Efron, "Why don't you come over tomorrow and I'll teach you how to ride?"

Of course, Efron accepted the once-in-a-lifetime invitation.

Former High School Musical star Ashley Tisdale proved she was all grown up in a sexy strapless bikini in Miami on Saturday.

The pretty blonde actress is in the Sunshine State to visit her boyfriend, Scott Speer, who is directing a music video in the hip Florida city.

PHOTOS: Ashley Tisdale Shows Off Her Bikini Bod In Miami

Dressed in a bright graphic-patterned bandeau top and electric blue bikini bottoms, Tisdale was spotting soaking up the sun and relaxing poolside.

She is no doubt enjoying the downtime before beginning work on the upcoming ABC sitcom, Under Construction, which was announced earlier this month.

PHOTOS: Julianne Hough & Ashley Tisdale Are Bikini Babes In Miami

Not only will Ashley star in the comedy that is inspired by her life, but she will also serve as executive producer.

The 26-year-old actress most recently starred as the voice of Candance Flynn in Disney’s Phineas and Ferb movie.

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Zac who?

Vanessa Hudgens and actor/model Austin Butler stole a few late night kisses over the weekend, and RadarOnline.com has the picture for you.

The gorgeous 22-year-old High School Musical star, who once dated co-star Zac Efron, was seen at the iconic Bob's Big Boy diner in beautiful downtown Burbank early Sunday with the Switched At Birth star, 20.

Ashley Tisdale has officially graduated from her High School Musical role!

The Disney actress spoke exclusively to Star magazine at the Luca Luca show at Mercedes-Benz Fashion Week, revealing that she is done playing Sharpay Evans, the role that sky-rocketed her to international fame.

“No,” the actress confirmed to Star when asked if she would reprise the role.  “I’m done.”

Zac Efron and Ashley Tisdale showed off two of the best bods in Hollywood Saturday, as they took to the beach in Malibu for an afternoon of fun and games.

Holding on to each other in the surf and laughing until they almost doubled over, the former High School Musical costars are definitely good friends.

PHOTOS:  Zac Efron & Ashley Tisdale Horse Around At Beach

Vanessa Hudgens has definitely graduated from High School Musical sweetheart to luscious leading lady.

In the April issue of Shape, Hudgens, now 22, dishes on everything from her love of Cheetos -- to her love of fashion -- to her love affair with former 'High School' hottie Zac Efron.

Shape hit the gym with the brunette beauty and was amazed as she lifted 50-pound kettlebells -- part of her grunt-worthy routine to keep those rock-hard abs and killer curves.

Vanessa Hudgens has ditched her squeaky-clean image in favor of a sexier, tattooed look, but RadarOnline.com has the cute childhood pictures before she was even famous.

PHOTOS: Vanessa Hudgens -- Before She Was Famous

The newly single actress has come a long way since her days at Disney, but it was clear from an early age, that Hudgens had star potential.

Vanessa Hudgens got tattooed by renowned artist BangBang, and RadarOnline.com has the pictures for you.

PHOTOS: See Vanessa Hudgen’s Tattoo

The gorgeous 22-year-old High School Musical star, who’s dated her dreamy co-star Zac Efron, kept her head down as the artist inked a beautiful butterfly on the back of the starlet’s neck.

BangBang, who is based in Manhattan, has also done work on Rihanna.

Next up for Hudgens on the silver screen is Journey 2: The Mysterious Island, in which she co-stars with The Kids Are Alright's Josh Hutcherson, wrestler-turned-film star Dwayne Johnson and the legendary Michael Caine. The film hits theaters September 23, 2011.

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