Metallica have released a lot of divisive albums over the course of their career, but Metallica — better known as The Black Album, though not technically titled as such — marks the clearest partition in their catalog. This is the moment at which Metallica’s decade-long rags-to-riches story reached its crescendo.

Though hindsight gives The Black Album the look of a brazen cash-in, it was a daring move for Metallica at the time. Indeed, fans of their first four albums abandoned them in droves when it came out, and producer Bob Rock gelled so poorly with the band that they swore at the time never to work with him again.

But work with Rock they did, and The Black Album’s difficult nascence bore dividends. Though it is far less ambitious and consistent than the works that precede it, its five hit singles deliver a remarkable balance of heaviness and accessibility. The Black Album is impeccably calibrated to titillate mainstream listeners without scaring them off. It is the ultimate metal album for dads, kid cousins, and R.E.M. fans. There’s a reason that “Enter Sandman” was such a knockout choice for Mariano Rivera’s entrance music.

In fact, with some 30 million copies sold, The Black Album is one of the most commercially productive recordings of all time. Despite Metallica’s vow, Rock would go on to produce their next three albums. The Black Album may have made Metallica genuine mainstream rock stars, but the success came with a price: No Metallica album since has been as commercially or artistically successful.