At first glance, Infected seems like a major departure for Swedish power metal kings Hammerfall.

The cover doesn't feature their hooded, hammer-wielding mascot, but instead has a horror-movie vibe, with a gray hand reaching upward and the band's logo replaced by block capitals in blood red.

And the first song continues the viral-horror theme; it's called "Patient Zero" and it's about a zombie invasion.

But it's setting the stage for a concept album that never quite comes together.

Yes, there are other songs on the album that return to the theme, like "Dia de los Muertos" (on which vocalist Joachim Cans sings in Spanish), but many tracks are generic power metal, lyrically speaking -- tales of love and heroism applicable to almost any circumstance.

Musically, though, it's quite a powerful record, with plenty of hard-charging tracks and relatively few turgid ballads.

"I Refuse" has all the power of a classic '80s anthem by Accept or Judas Priest, and "Immortalized" is built around a stomping riff that will get the band's hordes of fans headbanging like mad.

Some listeners, knowing Hammerfall's history of "metalizing" non-metal songs, might get worried seeing "Let's Get It On" in the track listing, but don't worry, it's not a Marvin Gaye cover.

It's just one more power metal anthem, on an album full of them.

Infected finds Hammerfall taking a few tentative steps in a different direction, but at heart they're still the same cheesy, fist-pumping, guitar-shredding band they've always been.