For twenty five years the big four was a piece of journalism. Then, on a Saturday in June 2010, at an airport outside Warsaw, the four of them played the same bill on the same day for the first time.
Sonisphere, 2010

The Sonisphere festival series put Metallica, Slayer, Megadeth and Anthrax on the same bill across Europe in the summer of 2010, beginning in Warsaw on 16 June and taking in Sofia, Athens, Zurich and several others.
The Sofia show was broadcast to cinemas worldwide and subsequently released, which is how most people saw it, and it ended with all four bands on stage together playing a Diamond Head song, which is exactly the right choice and almost certainly Lars Ulrich's.
Why it took twenty five years
Money, logistics and a certain amount of history. Four bands of that size on one bill means four sets of management, four booking agents, four crews and a negotiation about the running order that nobody wants to have.
There was also the small matter of Dave Mustaine having been thrown out of Metallica in 1983 and having spent the intervening decades saying so. The public reconciliation between Mustaine and the band was a real precondition, and it took most of the 2000s.
The American shows

The bill came to America in 2011: Indio in California in April, then Yankee Stadium in New York in September, which is about as complete a validation as this genre has ever received.
A music that had been distributed by post in 1982 and dropped by the industry in 1993 was, thirty years later, filling a baseball stadium in the city where one of the four bands had rehearsed above a bakery.
| Date | Where | Note |
|---|---|---|
| 16 June 2010 | Bemowo Airport, Warsaw | The first, after twenty five years |
| 22 June 2010 | Sofia, Bulgaria | Broadcast to cinemas, then released |
| Summer 2010 | Across Europe | Athens, Zurich, Bucharest and others |
| 23 April 2011 | Indio, California | The first American date |
| 14 September 2011 | Yankee Stadium, New York | The largest of them |
What the shows were actually like
Long, hot and enormous, by every account, and considerably better than a reunion of something that was never a unit had any right to be.
Anthrax opened, which is the correct order historically and was hard on a band who had just got their singer back. Megadeth played second and were, by most reports, in exceptional form. Slayer played third and did what Slayer do. Metallica headlined.
The encore, all four bands on stage playing "Am I Evil?", is the moment that justified the whole exercise: four bands who had spent thirty years being treated as a category, playing a song by a band from Stourbridge who never got paid for any of it.
What it meant
It turned a piece of journalism into a real thing. Whatever the phrase originally described, by 2011 it described four bands who had shared stages, played together and been photographed as a unit, and the audience had spent a quarter of a century believing in the bracket hard enough to make it true.
It also, incidentally, made a great deal of money and introduced the whole genre to a considerable number of people who had come for the headliner.
Whether it will happen again
Unlikely in that form. Slayer have retired and unretired for festival appearances, and the logistics that made 2010 difficult have not become easier.
There have been occasional partial reunions on festival bills since, and the reasonable expectation is that the four will continue to appear on the same posters without the specific event being recreated. The bracket that made it possible is explained in The Big Four of Thrash Explained, and the full account is in Los Angeles, New York and the Big Four.
The Sofia release
The Bulgarian show was filmed and broadcast live to cinemas on 22 June 2010 and released afterwards on video and audio, which makes it the definitive document of the whole exercise.
It is worth watching for the encore alone, and for the sight of four bands who had spent a quarter of a century being described as a unit discovering on stage that they quite liked each other. The performances are variable, as festival sets are, and the occasion carries it.
What the audience was
Older than anybody expected and larger. The crowds at these shows were substantially people in their thirties and forties who had bought the records in the 1980s, plus a considerable number of their children.
That is worth noting because it is the clearest evidence available that the collapse of 1992 removed the industry rather than the audience. Those people had not gone anywhere; there had simply been nothing to go to for fifteen years.
What the bill left out
One observation, made at the time by a good many people and worth repeating. A stage in 2010 containing Metallica, Slayer, Megadeth and Anthrax did not contain Exodus, who were there before three of them, or Kreator, who were making equivalent records in Germany at the same time, or Testament, who had been on the Clash of the Titans bills twenty years earlier.
The event confirmed the bracket rather than examining it, which was the point commercially and is a fair criticism artistically. The wider version that fixes some of this is in The Big 8 of Thrash.
What happened to the four afterwards
Metallica have continued as the largest touring act in metal. Anthrax released Worship Music in 2011 with Joey Belladonna back and have been in their best condition for decades since. Megadeth have continued through further line up changes. Slayer released one more album, toured farewell shows through 2019, and have since returned for occasional festival appearances.
None of the four has made a thrash record of real consequence since, which is not a criticism of bands in their sixties and is worth stating plainly in an article about a nostalgia event.
Sources and notes
Dates refer to the principal announced shows. The Sofia broadcast of 22 June 2010 was subsequently released commercially.