The Beatles' song catalog is one of the best-known and revered bodies of work in the whole of modern music, and the depth, variety, and timelessness of the songs this once-in-a-lifetime band produced make that catalog both a marvel and a treasure.

Everyone knows these songs, and everyone knows them in the original Beatles versions.

Those versions are there, shining in stone, and even when they show up in remixes like in the recent LOVE mashup, the original recordings echo unshakably in the mind.

Roberta Flack knows this.

On Let It Be Roberta: Roberta Flack Sings the Beatles, she tackles 12 of the group's songs -- 11 written by John Lennon and Paul McCartney and one written by George Harrison -- and she knows full well that she's dealing with the ghosts of the original versions.

She knows, and she addresses it by reconfiguring the 12 songs she's chosen to sing into fascinating new shapes and arrangements, not exactly escaping the original versions, but giving them a fresh new direction by jazzy shifts in the melodies, and pinning them to inventive and very contemporary rhythms and recording techniques.

Flack doesn't treat songs like "In My Life," "We Can Work It Out," and "I Should Have Known Better" like they're made of museum glass, and because of it, she stretches them into interesting new corners.

Not everything works -- Flack singing "Come Together" could never have been a good idea -- but what does work, and that's most of what's here, brings these Beatles songs delightfully into the 21st century.

Even though the ghosts of the original versions still echo here, they support rather than derail what Flack does with them.