There are three musical groups called The Shells

1) A 1960s motown pop group. (from Allmusic.com)

The Shells -- led by Nate Bouknight (aka "Little Nat") -- scored with a Top 30 hit with "Baby Oh Baby," charting for the tiny Johnson label in 1957. The group -- Bouknight, Randy Shade Alston (tenor), Bobby Nurse (tenor), Danny Small (bass), and Gus Geter(baritone) -- continued to wax impressive 45s into the early '60s without much commercial interest, including 1958's "Sippin' Soda" and 1959's "She Wasn't Meant for Me."

In 1960, "Baby Oh Baby" was given a rare second chance when record collector archivists/reissue producers Donn Fileti and Wayne Stierle reissued the track to give it a second chance, hitting the pop charts on its second time around, charting at number 21. The Shells then made a hasty comeback, recording a mix of soul and pop standards as well as straight-ahead doo wop, such as "Be Sure My Love" and "So Fine." 1961 brought another fine effort, "Explain It to Me," and in 1962, the quintet cut the popular "Happy Holiday" with Ray Jones (aka Ray Lamont Jones) taking over lead vocals. In 1963, the Josie label paired the group together with the Dubs for half an LP, The Dubs Meet the Shells, a battle of the bands album in the tradition of The Paragons Meet the Jesters).

2) An Austin-based pop act. From their myspace page:

The Shells have been playing 60's influenced pop in Texas for over five years. Since 1999 they have performed at CMJ 2000, SXSW 2005, and have self released two records. Their debut album was recorded by Centro-matic's Matt Pence and is available on the band's own Posteurocentric label. The follow-up 7" was recorded at home by Carlos Jackson and released on little mafia records in 2006.

"Multiple singers, lots of harmonizing, and a kind of country vibe to their pop-all that was missing was the campfire. And at the risk of offending them, they looked really really young, like 15-year olds trapped in 20-something bodies. I think it was the overwhelming optimisn exuded; all smiles, all infectious. Even the saddest bastard there had to appreciate watching the lovely keyboard/guitarist/singer chug a Shiner while keeping the beat with her tambourine before getting up to dance her ass off. That's multi-tasking at its finest. As I put it much less eloquently to the band members after the show, the Shells were fuckin' rad," - Rank and Revue.

"The Shells buzz with homespun Syd Barrett energy" - Greg Beets Austin Chronicle

http://myspace.com/theshells/

3) A New York City based trio of "Cosmo Country" gals.

From their MySpace page:

"The Shells, a trio consisting of young female performers Carrie Welling, Melanie Klaja, and Jessica Rae Waltz, are a completely original pop/folk-rock harmony group. Their original sound has appropriately been dubbed as “cosmo country”: a blending of city pop with country folk-rock and intricate harmonies. All three women stumbled upon an audition for a three-part harmony group back in 2005 while pursuing their individual careers in the arts. Four years in the making, The Shells have grown from simple a cappella harmonies to performing with a full band at renowned New York City venues such as The Knitting Factory, The Bitter End, Pianos, and Arlene’s Grocery. They released their debut album Written Roads on October 8, 2009.

Written Roads was produced by Ryan Williams, who has also worked with major industry artists such as Linkin Park. In addition, Williams played almost all the instruments on the album. All songs on Written Roads were penned by the different members, showing the ladies’ breadth of musical talent. "

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