The concert of Iron Maiden in Paris on Monday night was interrupted by an hour-long power outage.

The performance, which took place at the La Défense Arena, was being recorded for Maiden’s upcoming Run For Your Lives Tour film. Before the show, fans were notified that the concert would be phone-free, a move made to provide the “optimal viewing experience” for the film. However, what the band and its team didn’t anticipate was a massive blackout.

The incident took place as Iron Maiden was charging through their 1984 single “2 Minutes to Midnight” – ironic, considering the tune was released on the album Powerslave. Fans weren’t left in the dark for long, as backup generators kicked in. However, they only provided enough electricity for the house lights. The issue, reportedly part of a larger power outage affecting the arena’s neighborhood, took an extended time to fix.

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Initially, fans tried to make the best of it, clapping and cheering in an effort to get the band back onstage. However, as time ticked on, frustrations grew. Paris is in the midst of a heat wave, and reportedly the arena’s air conditioning remained off for an extended amount of time. According to one of Iron Maiden’s European fan clubs, many people had left by the time the band finally returned, roughly an hour after the initial power outage.

Maiden resumed with “Rime of the Ancient Mariner” and went on to play such classics as “Run to the Hills” and “The Trooper.” However, because of the delay, the band was pushed up against local curfew. Thus, authorities did not allow the metal legends to return for an encore.

Fans Sound Off After Iron Maiden Power Outage

On social media, attendees of the Paris show expressed their frustrations.

“We came all the way from Romania for this show. We spent a lot of money on f—ing Paris (which is expensive as we all know) just to be at this concert. We were waiting for this for so long. F— this,” wrote one fan. “It’s obviously not Maiden’s fault but oh is the frustration high!”

Another fan, clearly disappointed that standard Maiden encore songs like “Aces High” and “Fear of the Dark” were not performed, questioned the band’s choices once the concert resumed. “Sorry you CAN do better,” he wrote. “If time is critical then skip other songs.”

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Others described the scene as “absolutely disappointing” and a “wasted concert.” Many fans asked if there would be refunds, while others wondered if Maiden will now record a different performance for their concert film.

Still, there were a few fans who managed to find the silver lining to the power outage. An attendee named Laurent Lolo noted on Iron Maiden’s Facebook that the band seemed “even more motivated” when they returned, describing the whole thing as “surreal.” “What a performance… I’ve never heard it so powerful.”