Hughie and Jackie's big day is set to be turned on its head in a big way when Heather storms in and reveals a secret, take a sneak peek at the drama here.

Coming up on Wednesday's episode of Fair City, Hughie and Jackie look happy and relaxed as they prepare to tie the knot in front of their friends and family.

At a crucial point in the wedding ceremony when the celebrant is asking Hughie if there is any lawful impediment to marrying Jackie, Heather all of a sudden barges into the room.

"You can't marry her!", Heather blurts out. "I saw you with him..."

The congregation and Hughie and Jackie look suitably shocked by the revelation...

Fans can find out what happens next on Wednesday on RTÉ One at 8:00pm.

Fair City airs on RTÉ One on Sundays and Tuesdays to Thursdays.

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