‘San Andreas’ star Dwayne ‘the Rock’ Johnson officiates at longtime fan’s wedding

Dwayne “the Rock� Johnson has been on a promotional roll on the days leading up to the release of his flick “San Andreas,� in which everything is rocking and rolling.

He even married a longtime fan for the betterment of the movie. More on that later.

With girlfriend Lauren Hashian looking on Tuesday, he became the 283rd person to immortalize handprints and footprints in cement outside the TCL Chinese Theatre in Hollywood.

Thursday found him at “San Andreas’� London premiere, where he set a Guinness World Record by snapping 105 selfies in three minutes (all of them in focus, no blurring, showing the full, recognizable face and neck of participants, as verified by a Guinness type who monitors such things).

Something audiences might want to monitor: Johnson told Variety that all the earthquake-related stuff could actually happen.

“We had the top seismologists challenge the script,� he told the trade. “They walked away saying everything in this script is plausible, including the tsunami. I had never gone into a project that had that level of research and detail by the experts.�

Something that wasn’t plausible but wound up actually happening was the aforementioned wedding, a video of which was posted to YouTube on Thursday. Johnson himself officiated over the knot-tying between superfan buddy and “The Screen Junkies Show� correspondent, Nick Mundy, and Mundy’s fiancee, Dilara Karabas, in what the star called a “pranking it forward� situation.

Johnson was authorized to do the deed, and a notary was on hand to make everything official. Friends and family were brought in secretly and seated on either side of the aisle.

The wedding was set up as a nightmare situation that found Mundy scrambling during the “San Andreas� junket to salvage the day for “The Screen Junkies Show� after the Rock didn’t show up for an “elaborate� bit that had supposedly been planned.

Along the way, as the crew frantically pitched last-minute ideas, the unsuspecting groom wound up drinking movie-junket beer and changing into American-flag pants. “I just feel like we dropped the ball ...,� Mundy said. “What’s this episode going to be, a thumbnail of me crying?�

Then, at the moment of the most intense desperation, the Rock did show up, dressed to the nines.

“I’ve got a little surprise for you. Just when you thought the day was going to be terrible, it actually is going to be the greatest day of your life,� Johnson said, escorting Mundy into a room set up for a wedding ceremony.

A suit jacket was on hand for the shocked groom, he borrowed a comb, the Rock walked him down the aisle, the bride wore white and the familiar words “Dearly beloved� kicked off a ceremony during which -- surprise -- the actor/officiant promoted “San Andreas.�

“I love you so much, and I can’t wait to do weird stuff with you for the rest of my life,� Mundy told Karabas as they exchanged vows.

“This is cool. Because it’s real,� Johnson said at the end, before the part when he pronounced them man and wife.

The Los Angeles premiere of “San Andreas,� which also stars Carla Gugino, Alexandra Daddario and “Arrow� actor Colton Haynes, is set for Tuesday. Afraid a tsunami might wipe out all the multiplexes before the film hits U.S. theaters May 29? Better head to Mexico City, where it opens Saturday.

Follow Christie D’Zurilla on Twitter @theCDZ and Google+. Follow the Ministry of Gossip on Twitter @LATcelebs.

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