Without Justin Timberlake, we might all have been without sexy, since, regrettably, no one else brought it back this summer. But the confident declaration the he is “bringing sexyback” on “SexyBack,” the first single off his sophomore solo release, was only the beginning of Timberlake’s sexual revolution — he has crammed his panting lyrics, grinding synths and even GQ-esque liner art with sex. “FutureSex/LoveSounds” shows that he has explored this elusive thing which he terms “sexy.” What is sexy? Perhaps Timberlake’s defiance of proper grammar is further proof of just how sexy he is.

No one may really know what sexy means, but one thing is for sure: Justin Timberlake knows how to get what he wants. He began humbly as a member of N*SYNC and defied all expectations with this solo debut, “Justified,” in 2002. He packed that album with a resolute punch, channeling the vibrant falsetto of Michael Jackson in his heyday, and delivered a handful of hits. Though still subtle, he let the sex seep into the off-beat “Like I Love You” and the soulful “Senorita,” and then took it down several notches and won our allegiance with his crooning on “Cry Me a River.”

On “FutureSex/LoveSounds,” he takes it all one step further. His lyrics could be evidence of his maturity, but more likely indicate his transformation into a true sexual predator. His beats are more complicated, as he layers several aural elements over one another. And his work with Timbaland, the default producer of all this summer’s hits, proved beneficial. Timberlake’s sound has grown, and his scope has broadened (certainly thanks to the productive elements introduced by Timbaland), resulting in a second album that will remain both on national radio stations and your iTunes for years to come.

The carnal motif is quite blatant on the record. Considering his most recent Rolling Stone cover states “Wet Dream: The New King of Sex Gets Loose,” what else did you expect? The titles of the album and the first three tracks all include the S word, all songs except for one (the misguided and maudlin anti-drug ballad “Losing My Way,” about the dangers of cocaine) are about sex, and Timberlake always backs each song with a music video chock-full of gyrating hips and undulating bodies. Yet, at times, his approach is a bit juvenile. He emphatically declares, “See everybody says you’re hot baby, but can you make it hot for me?” on the title track and, “She’s freaky and she knows it/ She’s freaky and I like it” on “LoveStoned/ I Think She Knows Interlude.” Not very suave, JT.

Still, Timberlake’s ambition shines through on this record. Sure, all his songs are a bit formulaic, but what’s wrong with following a formula if it works? His singles prove he knows all the elements of a surefire pop song — a solid hook and catchy lyrics, complemented by an attractive personality — and he capitalizes on it. “SexyBack,” hands down the most memorable single of the summer, has the staying power to carry through the fall. Timberlake stutters and pants all over the place, yet he and Timbaland still churn out a power pop anthem.

“LoveStoned/ I Think She Knows Interlude” presents two songs in one. It begins a caustic dance track (“LoveStoned”) and slowly evolves into a sweet ballad (“I Think She Knows”), still centered around the same chorus. The juxtaposition of the brash and the melancholic serves as a perfect metaphor for Timberlake himself and the image he projects: On the one hand there’s the boy in the boy band, the former Mickey Mouse Club Member, and on the other is his newer “mature” stance, the one with a healthy dose of danger and a plethora of pelvic thrusts.

There are still many questions surrounding Timberlake’s latest album. Why are all the songs so long (no track clocks in under four minutes)? Why do most tracks collapse into a weak R&B drone? Is the pedantic “Losing My Way” really necessary? What’s with the gratuitous use of the slash? And why does he feel the need to clumpallhiswordstogether? But these issues pale in comparison to the overwhelming vision and fun that he grants the listener. No one knows where sexy went or when exactly it disappeared, but Justin Timberlake deserves a hearty thank you for bringing it back.