John Bonham, the drummer for Led Zeppelin also known as "Bonzo" and "The Beast," died on Sept. 25, 1980, after choking on his own vomit at Jimmy Page's mansion in Windsor, England, which Page had just bought from the actor Michael Caine.

At the time, the band was preparing for a 20-city tour of the U.S. But days later, the remaining members announced that Led Zeppelin was no more.

"We can't go on without Bonham," Robert Plant said.

Page added: "We couldn't just replace somebody; it wasn't that sort of band."

Twenty-seven years passed before the band played another show. That show—a tribute to the late Ahmet Ertegun, the charismatic founder of Atlantic Records and a close friend of the band— took place at the O2 Arena in London on December 10, 2007. 20 million people applied for tickets in a worldwide lottery, and only 18,000 got them. Bonham's son Jason stood in on drums.

The concert has been preserved in the form of an epic two-hour film called Celebration Day, which premiered on Tuesday night at the Ziegfeld Theater in Manhattan. Earlier that day, a press preview was held at the Museum of Modern Art, followed by a tense and at times bizarre press conference with the band.

Throughout the screening, the assembled web, print and radio journalists shouted as if it were a real concert. ("Whoo!" "Yeah!" "Turn it up!") They clapped and hooted after every song. During "Stairway to Heaven," thousands of onscreen audience members whipped out their camera phones to record it. When someone at MoMA tried to do the same, a security guard snapped at him and he quickly turned it off.

The film's track list features 16 immortal Zeppelin hits, including "Since I've Been Loving You," "Black Dog," "Misty Mountain Top" and "Kashmir." Plant, wearing loose blue pants and no longer able to hit the banshee octaves of old, still made expert use of his harmonica in "Nobody's Fault But Mine." Page, white-haired and pouring sweat, brought out his Gibson double neck for "Stairway" and brandished his violin bow for "Dazed and Confused." Sitting at the drum kit in a tight black t-shirt bedazzled with rhinestones crosses, Jason Bonham looked less like his longhaired dad than a heavyweight UFC fighter whose confidence in himself outweighs his abilities, but he performed flawlessly. (The absence of "Moby Dick" on the set list relieved him of having to live up to The Beast's six-minute drum solos.)

After the screening, the assembled press was herded into the press conference. Every news outlet in New York seemed to be there. As the band walked on stage, someone said, "Holy shit, it's Led Zeppelin!"

At a press conference for the film in London last month, the band had evaded the question of whether they will reunite for a reunion tour. But that didn't stop journalists at MoMA from asking the same question in a variety of ways.

The Associated Press wondered whether the film got them thinking about, you know, something bigger for the band?

"We've been thinking about all sorts of things," Plant said. "We just can't remember what they were. Schmuck."

A radio host tried buttering them up ("You sound great, you look great") before suggesting that the film won't quench the thirst of those craving to see the band in the flesh. "What do you say to them?" he tried.

A lengthy silence ensued.

"Is anybody going to say anything?" the moderator said.

Later, when a reporter for CNN cut the preamble and went for it ("Why is it so hard to come together again?") he was met with even stonier silence. Another reporter, in if-you-can't-beat-em-join-em mode, piped up in the rockers' defense: "It's been answered a million times, sir!"

Plant came closest to offering an answer when he said, in response to a different question: "If we're capable of doing something, in our own time, that will be what will happen. So any inane questions from people who are from syndicated outlets, you should just really think about what it takes to answer a question like that in one second. We know what we've got, you know."

The original members remained pretty much in character. Jones, earnest and reliable, noted that playing "Kashmir" during the concert was "nice" because "I got to sit down" at the keyboard. Page, looking like Karl Lagerfeld in black glasses and a black scarf, seemed to confirm his continued interest in the occult. Plant, his gold locks now streaked with grey, added an air of "This is Spinal Tap" to the proceedings with a series of one-liners and strange non-sequiturs.

Apropos of nothing, he noted the presence of a masseuse in the crowd ("That's ever so exciting"). Asked why the band was so sensitive to journalistic criticism—a question posed by no less than Carol Miller, creator of "Get the Led Out" on Q104.3—Plant said simply: "Well, we were." After Bonham recalled a few fond moments fromThe Song Remains the Same, another concert film shot at Madison Square Garden in 1973, Plant said: "I wanted to know what happened to that blonde chick."

It was easy to imagine the ghost of John Bonham looking down on the news conference with naked contempt, wishing he could punch every journalist—and maybe Robert Plant—in the face.

Bonham often played concerts with a plastic bag full of cocaine between his legs. At bars, he was known to order 20 Black Russians and drink the first 10 immediately. On several occasions he stuck a gun into the back of Glenn Hughes, the bassist for Deep Purple, after accusing him of sleeping with his wife. The Plaza Hotel in New York demanded a $10,000 deposit whenever Bonham stayed there, before finally banning him outright after he threw TVs and furniture off his balcony onto the sidewalk below.

"There's no question that what you've got here is a super-sensitive guy," the Black Sabbath drummer Bill Ward once told British journalist Mick Wall, author of the Zeppelin biography When Giants Walked the Earth.

But the gentler side of the drummer's spirit endures in Jason Bonham, who spoke lovingly of his dad and the band he grew up idolizing, before meekly admitting his aviator shades contained prescription lenses.

Toward the end of the conference, Plant shared a memory of his childhood friend and former bandmate.

"John used to say to me: 'You're not very good, Planty. So just go out there and look good.' And you know? He was right."

Watch the video below: