Keely Smith, the groundbreaking musical partner of Louis Prima who enjoyed a late in life rediscovery as a jazz singer, died Saturday in Palm Springs of apparent heart failure. She was 89.

The “girl singer” in Prima’s band beginning in 1948, her deadpan and demure style played the foil to Prima’s over-the-top antics and manic singing style. Their music, a unique blend of jump blues, early rock & roll and jazz, was fused with stereotypical husband-wife humor of the day, the sort popularized by Lucille Ball and Jackie Gleason, that would connect with audiences on stage, television and film.

Smith, a native of Norfolk, Va., and Prima, a trumpeter-singer from New Orleans, were the first major act to call Las Vegas home, setting up at the Sahara Hotel with a band led by saxophonist Sam Butera. By the late ‘50s they were the most popular act in town and, at the first Grammy Awards in 1959, the two won the Best Performance By a Vocal Group or Chorus trophy for their version of “That Old Black Magic,” their only Top 40 hit together.

Prima and Smith recorded together, first on Capitol, then Dot, from 1956 to 1961, releasing albums such as The Wildest! and The Wildest Show At Tahoe. The two were regulars on variety TV shows and made a film together, Hey Boy! Hey Girl!, that featured some of their best known duets, the title track, “Oh, Marie” and “Banana Split for My Baby.”

Songs they recorded together would, decades later, be hits for David Lee Roth and Brian Setzer, and secure multiple prominent syncs in commercials and films, most notably Martin Scorsese’s Casino. Their relationship was chronicled in the stage show Louis & Keely: “Live” at the Sahara that had multiple runs at the Geffen Playhouse in Los Angeles.

Smith, who married Prima in 1953 and was divorced in 1961, had a concurrent solo career beginning with 1957’s I Wish You Love. Frank Sinatra was a fan and she worked with his arrangers, Nelson Riddle and Billy May, on her Capitol albums before moving to Dot and then to Sinatra’s Reprise where he gave Smith her own imprint, Keely’s Records. She released four albums before she retired in 1965 after marrying producer/singer/label owner Jimmy Bowen.

Smith returned to recording in 1985, when Fantasy released I’m in Love Again featuring a band of top-notch West Coast jazz musicians. It would be another 15 years before she returned to the studio, making four albums for Concord between 2000 and 2005.

Her 2001 album Keely Sings Sinatra received a Grammy nom and she appeared on the 50th Grammy Awards telecast in 2008 to duet with Kid Rock on “That Old Black Magic.”

Prior to retiring from performing five years ago, Smith had become a fixture on the jazz club/cabaret circuit. In 2006, she received the Society of Singers’ Lifetime Achievement Award.