Frank Bello recounts how Metallica brought Anthrax back to life with a "kick in the ass".

Frank Bello has incredible memories of The Big Four , which featured some of the biggest names in thrash metal: Anthrax , Slayer , and Megadeth Metallica 's call for a series of historic shows.

The show held in Bulgaria on July 22, 2010, was immortalized on DVD and shows one of the most memorable moments for the Anthrax bassist. During the performance of "Am I Evil?", a Diamond Head with all the bands on stage, James Hetfield and Bello shared a genuine exchange of emotion and love for music.

“I remember James looking at me, or almost looking at me, beckoning me over, kind of head-butting with his eyes. That was a celebration of that song and, even to this day, I say in interviews: I take my hat off to Metallica because they didn't have to do that. They were big enough to bring all of us [on tour],” the musician told Talk Toomey (via Ultimate Guitar) .

Beyond the memories and display of humility from Metallica, those shows also marked a turning point for Anthrax. The band hadn't released new studio albums since We've Come for You All (2003) and had just welcomed Joey Belladonna back on vocals for the third time.

The Big Four tour gave Anthrax the kick in the pants [of encouragement] to be a band again and release new music, to really have cohesion again. There’s a lot I’m grateful for, it meant more than many people think,” Bello concluded.

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