Lauren reveals she was locked in the basement at Speidi’s wedding

When Heidi Montag and Spencer Pratt tied the knot back in 2009, no one expected Heidi's frenemy, Lauren Conrad, to make an appearance, so viewers fell all over themselves when LC rocked up to the church apparently wishing nothing but happiness for her former BFF.

And while it may have looked all sweetness and light on screen, it sounds like the reality of that infamous day in Pasadena was fairly different.

Opening up during a revealing interview with US Weekly,  30-year-old Lauren explained that her experience of Speidi's special day was a nightmare from start to finish.

"The power went out, the generator went out and I said, 'I need to leave!'" the reality star revealed. "And producers wouldn't let me leave!"

While the show's producers deny this, Lauren ranted: "They literally locked me in the basement with two security guards and wouldn't let me leave! And I was like, 'You can't keep me here!' I was throwing a fit!"

Oh, and that poignant moment where Lauren leaves through the side door and Kristin Cavallari takes her place with other cast members at the front of the church?

Yeah, that was less to do with the show's arc, and more to do with Lauren's pressing schedule.

"At that point, this wasn't really my life anymore, and I left out the church's side door," she explained. "So that's why in the final scene, I'm not leaving with everyone else – I'm taking a side exit out because I had a car waiting, and I needed to leave."

So, now you know!