From the post-post-punk of their early EPs to Silent Alarm's sprawl of sounds and ideas, Bloc Party has never shied away from reinventing their music.

They continue to evolve on A Weekend in the City, an unashamedly ambitious, emotional album that builds on where they've been before but still feels like a departure.

Silent Alarm's eclecticism was one of its biggest strengths; not knowing exactly which Bloc Party you were going to get from song to song -- arty punks, unabashed romantics, or righteously angry rockers -- made for thrilling listening.

They make the earnest, anthemic sound that was on the fringes of Silent Alarm the heart of A Weekend in the City, and it works remarkably well.

It helps that the band's feelings are as focused as the music is.

A Weekend in the City revolves around Kele Okereke's thoughts on life in 21st century London; in his eyes, it's a few highs and moments of belonging, surrounded by a lot of loneliness and disappointment -- not to mention racism, homophobia, and religious hypocrisy.

On A Weekend in the City, Bloc Party is sadder, wiser, and more heart-on-sleeve than ever -- almost embarrassingly so, especially when compared to their aloof post-punk influences.

The album's opening salvo, "Song for Clay (Disappear Here)," immediately signals that vulnerable is the new brash: "I am trying to be heroic in an age of modernity," Okereke whispers, backed by tremulous keyboards and guitars.

Even when the song unfolds into searing rock, it stays intimate and implosive.

Okereke still sings like there's no time to waste, but his songwriting is tempered by experience.

He's become a striking lyricist, conveying ambivalence and yearning in remarkably direct terms.

Over "Waiting for the 7:18"'s wintry pizzicato strings and glockenspiel, he sings, "If I could do it again, I'd climb more trees/I'd pick and I'd eat more wild blackberries"; on "Kreuzberg," he sums up the hollowness that follows a string of one-night stands: "What is this love? Why can I never hold it? Did it really run out in those strangers' bedrooms?" The hopeful songs at the end of the album are just as eloquent, especially "I Still Remember," which wraps a complex attraction between two schoolboys in a sweet, almost singsong melody: "Every park bench screams your name/I kept your tie." Indeed, A Weekend in the City is often more remarkable for its emotional impact than its actual music, though Jacknife Lee's lush, layered production suits the album's scope (and just happens to be very radio-friendly as well).

Many of the songs follow a predictable formula of hushed verses and big choruses, and while Matt Tong's drumming adds some bite to the album's slickness, the riffs throughout A Weekend in the City are distressingly similar to each other (although "Hunting for Witches"' depiction of thoughtless paranoia makes it a standout).

A few tracks explore new sonic territory; not surprisingly, they're the ones that convey druggy escapism.

"On"'s luminosity blurs the line between being high on drugs or a person, while "The Prayer" distills the ritualistic feel of dancing in a packed club with its massed vocals, heavy drums, and splattered guitars; later, "Where Is Home?" uses these sounds to express mournful anger instead of elation.

Bloc Party fans who responded to their dark, angular art-pop might be disappointed, at least at first, with A Weekend in the City.

This album isn't as brash or immediate as the band's earlier work, but its gradual move from alienation to connection and hope is just as bold as Silent Alarm, and possibly even more resonant.