Hundreds of people gathered at City Beach Function Centre on Saturday afternoon for two weddings, waiting for the brides and grooms to arrive when the heavens opened around 5.30pm.

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Water began gushing in and down the walls, outdoor furniture was picked up and smashed about, before the power went out cloaking all in darkness and subsequently setting the fire alarms off.

Pro Sound and Lighting's Claude Spinelli was hired for one of the parties and said his "heart just split in half" to see the anguish on both brides faces.

"The music stopped, the kitchen stopped, everything stopped," he said. "But I believe in the show must go on, and when it's someone's special day you can't send them home."

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When Mr Spinelli saw one of the brides in tears he confidently told her everything would be fine, and "this will be the wedding of a lifetime".

"Everyone was just standing there watching her cry, and I don't know what came over me - some sort of superhero," he said. "'So I said 'we're going to give this a shot and make it happen'."

He raced back to his shop on Auburn Street and grabbed as many battery-powered lights as possible, generators and portable PA systems to try and bring life back to both parties.

Operations manager Therese Ly initially had hesitations about whether the DJ's plan would work, but everyone - including some guests - just "kicked into action" to restart the party.

"I was literally dripping with water trying to get sandbags in the rain, we had guests squeegeeing water with mops," she said.

"We were a little worried. We also had the fire alarms going off so we had the fire brigade out, so we had the couples taking photos with the fire truck - it was all happening."

Thankfully there was still gas available in the kitchen and with ad hoc lighting set up any food that was able to be cooked in a deep fryer or on a stove top was able to be sent out to ensure guests were fed.

At the time the Mercury spoke with Mrs Ly she was yet to assess the physical damage to the building but anticipated there would be extensive water damage to carpets and potentially damage to the balconies as outdoor furniture had been flying about.

She said Mr Spinelli was a "superhero" and they wouldn't have been able to pull it off without him.

"Without the lighting and the music we would not have been able to finish ... it made the night of their dreams a little different but it happened."

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