On March 26, 2004, Van Halen announced they would be heading on tour that summer and erstwhile singer Sammy Hagar was back in the fold, eight years after his rancorous departure from the band.

On that day, Hagar called in to Howard Stern’s radio show to provide his confirmation, admitting the band had spent the previous three months making music together at Eddie Van Halen’s studio and clubhouse 5150 on the guitarist’s property in Los Angeles.

In the course of the conversation, Hagar remarked that Eddie Van Halen was “healthy and playing better than ever,” and they had written and recorded several new songs for an upcoming compilation to coincide with the tour: The Best of Both Worlds, which wound up featuring three new tunes. He mentioned that one of the songs – “It’s About Time” – would be the first to be released.

On June 15 that year, Van Halen fans heard the results.

Listen to Van Halen's 'It's About Time'

“It’s About Time” kicks off with Eddie Van Halen playing a crunchy guitar, in drop-D tuning so it sounds extra low and mean. Hagar comes in, singing “Turn, turn, turn, turn,” before Alex Van Halen hits his snare drum, Eddie plays a couple harmonics and the band leans into the first verse.

“It’s About Time” is predictably guitar-heavy, layered with single-note riffs under the main one and different picking techniques to create a rhythmic counterpoint to the straight beat. There’s a little production sheen on the track, no doubt courtesy of coproducer Glen Ballard, but overall it sounds like one would expect Van Halen to sound in the early '00s – a modern take on their classic hard rock.

Hagar takes a self-referential path with the lyrics, almost as if he had sat in the middle of 5150, spun his chair around slowly and simply reported what he saw. The track is peppered with references to the band’s break with the singer and with their eventual reunion: “Last time, wrong time,” “Yeah, but this time's our time,” “Get up, turn your clock back / Paint it red on black,” “Right now makin' up for lost time,” “We're 'bout to make it up to you big time.” Every other line is some variation of “We’re back together, everything’s cool and we’re coming to your town soon.”

Everything wasn’t so cool, though, at least not for long. The 80-date tour on which the band embarked was rife with hostility and poor performances, due largely to Eddie Van Halen’s alcoholism. At the jaunt’s conclusion, Hagar and bassist Michael Anthony (who did not play on the three new Best of Both Worlds songs) departed, never to return to the band again.

The seeds of that trouble likely began in the studio, where it took a mighty effort for Van Halen to get himself together enough to play. In his 2011 memoir, Red: My Uncensored Life in Rock, Hagar recalled with evident frustration, “We had [new songs] ready within one week. It took three months for Ed to do the guitar parts to three songs and a couple of solos. ... I went in and knocked out my vocals on all three songs in two hours. [Michael Anthony] came in and we did all the backgrounds in another two hours. Eddie was still asleep. By the time he came down, we were finished. They spent the next three months doing Eddie's guitars.”

Some black-and-white footage cobbled together from the sessions - shot by filmmaker Andrew Bennett, ostensibly to make a video for “It’s About Time” - can be found online. The film shows Hagar and the Van Halen brothers in the studio, with Eddie studiously working on guitar and bass parts with Ballard, Hagar singing lyrics into a handheld microphone and Alex playing drums.

Watch a Video From Van Halen's 'It's About Time' Sessions

The video includes a few other behind-the-scenes moments that may have portended trouble. In one, Eddie Van Halen says, “This is fuckin’ reality – not scripted,” as he carries a wine bottle from the studio’s kitchen; Hagar noted in Red that the guitarist would drink wine right from the bottle all day long.

Another, perhaps more telling scene finds Van Halen and Hagar outside the studio at night, with the guitarist about to get behind the wheel of a car. Hagar asks, “Hey, Eddie, where are you going, man?” The guitarist responds, “I’m done, man. It’s time for you to sing, bitch.”

Whether that cutting reply was made in jest is not apparent, though when coupled with Hagar’s recollections of the sessions and what eventually came of the 2004 tour, it’s not difficult to imagine tension between the two men surfacing, even at the beginning of the reunion.

That’s sad, because for Van Halen fans – particularly those who loved Hagar’s first go-round with the band – “It’s About Time” sounded like a positive beginning to a new chapter in Van Halen’s story. Knowing what we know now, though, the unhappy ending that eventually went down was probably inevitable.

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