How do you follow up two critically acclaimed albums?

Release two more … simultaneously.

The Red Hot Chili Peppers take perhaps the biggest risk of their lengthy careers, delving into double album territory with Stadium Arcadium. RHCP join the ranks of Led Zeppelin, the Beatles, OutKast, Smashing Pumpkins and, most recently, the Foo Fighters by releasing two full CDs, dubbed "Jupiter" and "Mars."

And maybe it's most fitting that the problem inherent with the double album is the only real gripe with Stadium Arcadium: With so many songs (28, actually), it's inevitable that a few are going to be nothing more than filler.

Despite their best efforts, the Chili Peppers fall to the curse of their ninth studio album. That's not to say the rest of the material is bad — far from it. Stadium Arcadium is everything the band said it was going to be. This is some of their best work, showcasing a tremendous amount of effort and passion for the music they are playing.

The experience starts with "Dani California," the first single released off the discs. Picking up where "Californication" and "By the Way" left off, "Dani California" tells the final leg of Dani's story. The song is decent, but as is the case with most singles, it is certainly not the best to be found on the album. It serves as little more than an appetizer for the feast of funk rock yet to come.

"Snow (Hey Oh)" is a somewhat lighter song, not unlike everything the Chilis have already done. At the same time, it's somehow still unique in its own right. Guitarist John Frusciante's strumming plays out a soft, yet complex melody beneath Kiedis' trademark layered vocals.

The titular "Stadium Arcadium" is good but really serves best as an example of just how far Kiedis has come over the years. No longer relegated to stumbling over words and shouting, he has developed an arguably beautiful voice, which is showcased wonderfully on both this track and the entire album.

The rest of "Jupiter" is somewhat hit-or-miss. "Hump de Bump" boasts a funky beat that would make even James Brown proud, "Especially in Michigan" is painfully bad except for an incredible hook, and "Torture Me" sees the Chilis rock harder than they have in quite some time.

The disc winds down with "Warlocks" and "C'mon Girl" but hits one final highlight in "Wet Sand." It slows the pace of the album once more, but this time, it's a welcome change rather than an awkward transition. And in the last leg of the song, as Kiedis belts what can best be discerned as "You don't foam in the wet sand / you don't foam at all" over what sounds like a harpsichord, it can only be described as incredible.

But if "Jupiter" is the mixed bag of this pair, "Mars" is the solid gold. From start to finish, disc two of Stadium Arcadium stands as some of the finest work the Chili Peppers have done to date. Well, maybe not from start to finish — one has to wonder what Kiedis and company were thinking when they decided to include complete duds like "If" and "Animal Bar."

Building from the powerful kick that "Desecration Smile" packs, RHCP move in a more deliberate, calculated pace with "Mars." The first four tracks are all bona fide hits, alternating between soft, sleek ballads and thumping funk rockers. "Tell Me Baby" has its roots buried both in old-and new-school Chili Peppers sounds, borrowing from both extremes. The chorus is a silky smooth yin to the rest of the song's jarring, funky yang.

"Hard to Concentrate" showcases what sounds like Kiedis reading poetry at an open mic night, with an acoustic version from the Chili Peppers in tow. This is easily the most romantic song the group has ever created (right next to "Purple Stain," of course), with Kiedis soulfully singing: "Finally you have found something perfect / and finally you have found yourself with me / Will you agree to take this man into your world? / And now we are as one."

"Readymade" isn't particularly memorable outside of Frusciante's mesmerizing licks and the fact that they actually use cowbell in the song. The rest of "Mars" winds down with a space age, surfer-like "Make You Feel Better," "We Believe" and its Kiedis backing chorus, and "Turn it Again."

The entire musical experience ends with the superb "Death of a Martian," which can only be described as space-rock infused with heavy doses of funk and punk. Kiedis' lengthy tirade toward the end of the song is a bit bizarre but somehow works at the same time. After the musical journey he and the rest of the Chili Peppers just took you on, it's almost as if you owe it to him to listen to a little rant.

So is Stadium Arcadium the masterpiece the band was claiming it would be? No. But at the same time, these two discs represent some of the finest work the Red Hot Chili Peppers have recorded up until this point — which is saying quite a bit.

Rating: 4 out of 5