Green Day nostalgia is in the air because their breakthrough album Dookie turned 25 this year. The band has been selling old gear from the Dookie era (including mud-stained speakers from their Woodstock '94 set, which is both Green Day nostalgia and Woodstock nostalgia), and the band also unleashed a new Dookie-themed guitar pedal. Dookie turned Green Day into stars, it's massively influential, it helped get so many people into punk, and it's home to five of their biggest and most memorable pre-American Idiot singles. For all of these reasons, it's generally considered their most classic album, but I'd argue that Green Day one-upped themselves just a few months later. Their best album is not the influential, hits-filled Dookie (or American Idiot for that matter), but Dookie's quickly-released followup Insomniac.

Dookie deserves all the credit it gets. For me personally, it was one of my first punk albums and I can't imagine where I'd be today without it. You still hear about half of its songs at bars, parties, karaoke, etc, and if you're under the age of 35 and you play in a punk band, chances are this album was and still is a very big deal to you. Its songs are deeply ingrained in the DNA of modern punk, and dissing it at this point feels like an eyeroll-worthy attempt at being contrarian. That said, like lots of albums this immensely popular, it's easy to get tired of hearing Dookie or at least feeling like you don't have much of a reason to put it on at home anymore. I unintentionally hear Dookie songs multiple times a year just by leaving the house, I don't really need to come home and put it on myself too. If you've never listened to Green Day, it might still be the best place to start, but once you've absorbed the whole catalog, you may find that Insomniac holds up better. Part of that is because you hear it less -- it didn't match the success of Dookie and it has less hits (Insomniac's only real huge hit is "Brain Stew," which got even more of a boost when a remixed version appeared in the 1998 Godzilla movie) -- but that's not the only reason. It's not exactly the In Utero to Dookie's Nevermind or the Pinkerton to Dookie's Blue Album or the Kid A to Dookie's OK Computer, but it is just a bit darker and harder than its predecessor and that goes a long way. Dookie can start to sound too bubblegummy after a while, but Insomniac manages to deliver plenty of singalong punk songs without falling into that same trap. It was also recorded better, and the band played better. They hit the studio in December 1994, just weeks after wrapping up their nearly-year-long tour schedule supporting Dookie, and they were unsurprisingly on fire at this point. They had just spent months playing tons of shows to the biggest crowds of their career (including the aforementioned Woodstock '94), which was all the prep they needed to quickly bang out a rock-solid followup to an instant classic. It gets overlooked because it came so soon after Dookie, and because the next album (1997's Nimrod) introduced Green Day to even more non-punk audiences with its destined-to-be-sung-at-graduations song "Time Of Your Life." But among its 14 tracks are some of -- if not the -- best songs Green Day ever wrote.

Like Dookie, Insomniac opens with a now-iconic drum fill, and if it sounds right off the bat that Tre Cool is hitting harder than he had ever hit before, he himself would agree. As he told Rolling Stone around the time of the album's release, he credited it to having a kid. "I can hit the drums harder than I ever thought I could. Having a kid is trying – you have to watch your temper all the time – but it enhances the experience of playing in the band." Then the rest of the band comes in, and it's instant pop punk bliss. Billie Joe Armstrong's power chords sound sharper than ever, Mike Dirnt's basslines are more in the pocket than ever, and maybe the most noticeable improvement in Green Day's sound comes in on the chorus: the vocal harmonies. Billie Joe and Mike Dirnt's harmonies were admittedly a little shaky early on in Green Day's career, and though they had vastly improved them by Dookie, Insomniac was the moment they perfected them. By the time they branched out from punk and started delivering more complex vocal work, they were pros at harmonizing, and that all started on Insomniac.

It's clear from album opener "Armatage Shanks" alone that Green Day's songwriting took a turn for the slightly darker on Insomniac -- Billie Joe's lyrics have always had a dark side, but here his introvertedness and pessimism is matched by the tone of the music more than it was on Dookie -- and he managed to do this while only strengthening his knack for melodicism. The verse and the chorus on this song both come with a hook that rivals Green Day's bigger hits. That continues on the next two songs, "Brat" and "Stuck With Me," which make for the most relentless one-two-three punch of any Green Day album, and Insomniac has a handful of other should've-been hits like "Stuart and the Ave," "86," and "No Pride." Those songs hit the same pleasure points as "When I Come Around" and "Longview," and they're actually even tighter and punchier. It's hard to say for sure, but I bet if "Brat" and "Stuart and the Ave" were the ones all over MTV and the radio in the '90s, they'd be karaoke regulars today too. (The album's poppiest song and second biggest hit after "Brain Stew" was "Walking Contradiction," though admittedly I think that's one of Insomniac's weaker songs.) There's also an argument to be made that Green Day had developed an even more unique sound on these songs. Dookie earned Green Day their fair share of comparisons to the Buzzcocks, but by Insomniac it was undeniable that this was a band with an original sound of their own.

Along with those punchier songs, Insomniac had a slightly heavier -- and sometimes slower -- sound too. That's very evident on the aforementioned "Brain Stew," which sorrrrrrt of goes into alt-metal or grunge territory, but it's also there on "Geek Stink Breath" (which was also a minor hit), on the hard rock of "Bab's Uvula Who," and on the classic rock-ish "Panic Song." There's also "Jaded," which is usually packaged with "Brain Stew" as one big two-part song, and which is one of Green Day's hardest punk songs.

Insomniac was also the last time Green Day were a true punk band. Nimrod had its fair share of punk songs (including career highlight "The Grouch"), but it mostly saw them going in a lighter, more "rock" direction that got even lighter on Nimrod's 2000 followup, Warning. (And then they would come back four years later, fully reinvented as rock opera makers, with American Idiot. And the rest was not-very-punk history.) Insomniac closed the book on Green Day's punk roots, and it's still the best proof that Green Day really were just a great punk band, before the graduation ballads and the rock operas and the actual Broadway musicals. There's also a good argument to be made that the pre-Dookie stuff -- when Green Day were on Lookout! and playing shows at Gilman St. -- was Green Day at their most punk, but as good as the early material (especially Kerplunk) is, their tools weren't as sharp back then as they were on Insomniac. It might not be their most popular album, but it's the one where everything just clicked and fell into place so quickly. It sounds better and less dated than its rawer predecessors, and it's meaner and leaner than any Green Day album that followed. Of all the albums from the band's classic '90s run, it's the one that sounds most fresh today.

Watch some videos of Insomniac songs and stream the album below...