May 20, 2011 -- It was supposed to be the most incredible musical Broadway had ever seen, and it has yet to make it to opening night.
"Spider-Man: Turn Off the Dark" had a musical score written by U2's Bono and The Edge, stupendous set design and fantastic flying sequences that would rival Cirque du Soleil. But even though it's Broadway's most expensive production ever -- it reportedly cost $70 million -- it has also been riddled with problems.
"Spider-Man" has had six delayed openings, five injured cast members -- one of whom almost died in a fall -- and some of the worst reviews in Broadway history.
In their first television interview since the show opened for previews last November and director Julie Taymor left, Bono and The Edge said they agreed with much of the criticism of the show. The New York Post called "Spider-Man" an "epic flop" and the New York Times review said, "It may rank among the worst musicals ever made."
"It might have been a little hard for some other people around here to take that, but we don't disagree with the New York Times," Bono told "Nightline" anchor Cynthia McFadden. "That's the sort of stuff we were saying backstage."
That shocking insight is part of the reason for the recent departure of Taymor, the legendary director of "The Lion King" musical, who wrote and directed the original version of "Spider-Man." Taymor declined to comment for this story.
Watch the full story and see some of the incredible flying stunts featured in "Spider-Man: Turn Off the Dark" on "Nightline" tonight at 11:35 p.m. ET/PT
"Julie would not accept this," Bono said. "She got very close to it, so close, perhaps, that she couldn't see it. And we were going out and coming back and we could see very clearly what we thought were the problems and she didn't think they were as big a problem as we did."
Both Bono and The Edge praised Taymor's work and said they wanted her to be with them during their first foray into musical theater.
"Julie is an incredible artist, really a very gifted girl," Bono said. "I think it's -- it's a shame she's not with us to see it to its conclusion, because a lot of what's magic about it is hers."
"If it's a big success, I think it serves everybody involved and Julie, as well, because, you know, this show is so much about the contributions she made," The Edge added. "So I think the best thing we could do for the show and -- and for Julie is turn this into a success"
Last month, "Spider-Man's" producers closed the show for three weeks and brought in a new director, Phil McKinley, to fix it.
"Some people call me 'Spidey Doc,'" McKinley said.
The show certainly needed a jolt of inspiration. A song was added and the love story between Peter Parker and Mary-Jane Watson was further developed.
"The last version of 'Turn Off the Dark' had a lot of magic and mysterious stuff," Bono said. "It was beautiful actually, in so many ways. It just, it didn't cohere."
"This time you have a really clear story line," Bono continued. "You have characters that you're getting to know. The music is in a system where it's legible and there's lots of really obvious stuff that has been fixed."
Actor and dancer Chris Tierney, who is a stunt-double for the Spider-Man character in the flying scenes, almost died when his harness wasn't properly secured and he fell 30 feet from a ledge into a stage pit during a preview show in front of a shocked audience on Dec. 20, 2010.
"I broke three vertebrae, my lower vertebrae," he said. "I broke four ribs. I fractured my elbow -- my scapula, my elbow and my skull…got the scars to prove it."
In his first one-on-one interview since the accident, Tierney told Cynthia McFadden about that preview performance when he jumped and then realized he wasn't attached to anything.
"I went out for the jump. I'm contained by my tether and that's why I'm always, you know, it will stop me, and so...I always go for it," he said. "I didn't factor in somebody's mistake, you know, back there, and so yes, I took a dive, but it was worth it."
Injured Stuntman Chris Tierney Returns to 'Spider-Man'
After four months of intense rehabilitation and rest -- months ahead of schedule -- Tierney is back with the show and fearlessly going airborne once more.
"I can go 40 miles per hour, 45 miles per hour," he said. "I can also change the speed of how I fly and the impetus and how I go."
While the show's storyline has been revamped, Phil McKinley made it clear this was still "Julie's show." He also said the flying apparatuses the actors use to lunge through the air continues to astound audiences, and watching a live performance of "Spider-Man" is the closest to what you would see on a film set.
"It's amazing that they can do this kind of technology, you know, here in the theater," McKinley said. "What I think is unusual about all of the flying is that it is not theatrical flying. It is really film flying."
McKinley not only directed the award-winning musical, "Ben-Hur," in London, but also directed hundreds of Ringling Bros. and Barnum & Bailey circus performances. He said his experience helped him understand the technical aspects of the "Spider-Man" production.
"Directing the circus told me about how to, you know, work with and collaborate with large numbers of people," he said. "Circus performers always inspire me."
McKinley said the crew tests "every inch of line" every day and they are taking numerous precautions to keep their actors safe. While there have been no injuries since he started working on the show, he said the danger is still there.
"There is always a risk because you still are doing thrills," he said. "You still are doing very, very high-skilled, thrilled, flying, and so, of course, there is always going to be that risk factor."
"Spider-Man" debuted in its latest version last month and the cast and crew received a standing ovation from the preview audience. Opening night is currently scheduled for June 14.
"I love watching the audience when Spider-Man drops into the audience, the expressions on the faces," McKinley said. "I think that is what is fantastic about the show."