On Feb. 24, 2003, Lars Ulrich told Robert Trujillo, “We want you to be a real member of this band, not just a hired hand… we’d like to offer you, to show you how serious we are, offer you a million dollars to join our band right now.” With that, Trujillo became Metallica’s third – and now longest-serving – bass player. It had been a grueling experience for the former Ozzy Osbourne, Suicidal Tendencies and Infectious Grooves member, because not only did he have to endure a series of high-profile auditions, he was being filmed while he did it.

The moment Trujillo is hired remains one of the high points of Metallica movie Some Kind of Monster, often criticized for the way it appears to depict some of its members as weak-willed and lacking conviction. To be fair, though, the band were suffering issues that had nearly brought them to a split – frontman James Hetfield had gone to rehab, Ulrich was dealing with severe stress, and Jason Newsted, the previous bassist, left in 2001.

Trujillo had established a reputation as an insightful, driving musician during his time with Suicidal Tendencies, who were already at their peak when the then-24-year-old Trujillo joined in 1989. That led to his membership in their funk-metal offshoot Infectious Grooves, and later to a stint with Osbourne. So he was a known name by the time Newsted quit, citing personal issues and that years of touring had taken a physical toll on him.

Much later, Newsted revealed that Hetfield had personally intervened to block development of Newsted’s band Echobrain, and that had been the last straw. Hetfield later admitted that Newsted had been the focus of their grief over the death of Cliff Burton, who had died in a tour bus crash in 1986 and been replaced by Newsted just three weeks later. “We were brutal with him,” the frontman once said. “And it never ended, really.”

With an album in the works, Metallica decided to carry on without a full-time bassist, and producer Bob Rock filled in on studio sessions, which are seen in Some Kind of Monster. If the movie does anything well, it illustrates just how dysfunctional the band had become. Hetfield said after the fact, “A lot of times I'm not really comfortable with myself and seeing myself in the situations, but, man, I learned a lot about what I don't like about me. Which was good … And I think everyone involved in that movie pretty much felt the same way about themselves."

With the record that was to become St. Anger in the can, the band turned their thoughts to finding a fourth member – and it’s easy to understand why they were hoping for a new beginning, and how that had to include not making the mistakes they’d made with Newsted. The biggest band in the world could have just about anyone they wanted, and the shortlist included Eric Avery (Jane’s Addiction), Mike Inez (Alice in Chains), Pepper Keenan (Corrosion of Conformity), Danny Lohner (Nine Inch Nails), Scott Reeder (Kyuss), Chris Wyse (the Cult) and Twiggy Ramirez (Marilyn Manson). Trujillo was probably added to the list because he’d once spent a week surfing with guitarist Kirk Hammett – although he recalled the pair “didn’t talk about music much” during their vacation.

Trujillo had the dubious honor of being “the first man through the door,” as Ulrich says in the movie. “I’m kind of like the guinea pig,” the bassist replies with an awkward grin as he’s asked to explain, just like a normal job interview, what he thinks he can bring to the band. He later admitted that, having spent the previous day in the studio, then getting drunk with Ulrich, he was nursing a severe hangover. “Here I am with a pounding headache. James has just gone through this whole thing where, of course, he's sober, and the last person he wants to see anywhere near his band is a drunk Mexican. That would be me. … And I'm thinking, 'Lars did this to me, 'cause he was checking me out, to see if I could hang with him.' It was [a test]; it had to have been. … I’d go into the bathroom. I was throwing water on my face, slapping it, going, 'Oh, man, you've gotta… Hang in there. Hang in there.' 'Cause I really wanted to say, 'I can't do this right now, guys. I don't feel good. I really can't do this.'"

Fortunately, he’d previously worked with Metallica’s bass tech, Zach Harmon (who still works with him today), and with a friendly face to help him out he endured the audition. “We played 'Battery', and I think it helped me not be nervous," Trujillo said. "And that's what you see in the film, and everybody seems to think it was pretty slamming. But other than that, I was brain dead. If I could play, I was fine. But in communicating with Hetfield, 'cause he would come over to me and ask me questions, and I would come up with really stupid answers, because, literally, I was not all there." He also admitted the shirt he’s wearing in the movie had been given to him by Ulrich’s wife because the “funky” one he had “was not happening.”

Metallica found his performance convincing enough to bring him back for another audition, and then finally offer him the job. “The second time you came back was when I noticed: you make us play better, man,” Hetfield tells him in the movie. “You make us sound so much better, so solid.” Hammett adds, “You’re the chosen one” before Ulrich goes on to offer him the million-dollar advance. In a fan club video entitled Tru-hee-o for those struggling with pronunciation, he explained his confusion to have walked into a room to find the band and associates applauding him. “They were appreciating my look that day, I don’t know,” he joked. Ulrich said they’d wanted him in the room to avoid offering him the job by phone. “We’re now Metallica par excellence,” Hammett stated.

Trujillo’s furious and energetic stage presence soon became a mainstay of Metallica’s stage show, and it’s remained that way ever since. The band have released just three studio albums since he joined – 2008’s Death Magnetic, 2016’s Hardwired… to Self-Destruct and the controversial Lulu collaboration with Lou Reed in 2011 – but the two Metallica albums are undeniably impressive, a return to the raw emotion that made their name, and his contribution is highly apparent. “It just gelled, and it's still gelling,” Hetfield said last year. “And his personality is probably one of the best contributions, I think, to the band, 'cause he's so chill, he's so up for anything, he's always in there rehearsing. So he does fit in."

As one of the highest-profile bass guitarists in the world, he continues to fly the flag for the instrument. He made a documentary about his late hero, the virtuoso bassist Jaco Pastorius – and Trujillo’s son Tye last year became a temporary touring bassist for Korn at just 12 years old. Even Newsted has nothing but respect for the man who replaced him: “Robert's a great fuckin' bass player and he's always been a great bass player,” he said last year. “I’m down…He got in there and he can hang with those guys and make it sound like it does? Peace, peace, power to you.”

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