There is a palpable sense of multiple journeys at play in Louis & Keely: ‘Live’ at the Sahara, the Geffen Playhouse’s latest incarnation of the rousing and powerfully poignant jukebox biography of 1950s husband-and-wife crooners, the hyperkinetic bandleader Louis Prima (Anthony Crivello) and jazz stylist Keely Smith (Vanessa Claire Stewart).

One is the bittersweet transit of showbiz triumph to tragedy — an archetypal plotline of so many MGM backstage movie musicals of the ‘40s and ‘50s (i.e., Lady Be Good; A Star is Born) that writers Stewart, director Taylor Hackford and Jake Broder use to frame Prima and Smith’s tumultuous, May-December romance and their legendary seven-year stand at the Sahara Hotel’s Casbah Lounge in the 1950s.

In the case of Louis & Keely, the template proves particularly apt. The book cannily zeros in on the playfully combative stage dueling between Prima’s infectious, high-energy clowning and Smith’s affectations of deadpan exasperation as the key to both their Vegas success, as well as their undoing when Keely’s soaring solo-recording career unlocks Louis’ dormant insecurities and self-destructive demons.

Then there is the behind-the-scenes journey of the production itself. Originating in 2008 at East Hollywood’s 99-seat Sacred Fools Theater as an acclaimed piece of poetic, stage-musical minimalism, Hackford’s top-to-bottom, 2009 retooling at the Geffen resulted in a less certain version that was itself wholly re-revised (and partially rewritten by the director) for this main-stage edition.

What was once a lean, concert-styled entertainment in which the tumult of the couple’s marriage was conveyed entirely within the confines of their lounge act now resembles a more conventional and Broadway-friendly musical swelled by expository scenes and additional characters (Paul Perroni as Frank Sinatra, Erin Matthews as various other women in Prima’s life) and pumped-up production values (Christopher Ash’s crack lighting and projections; Hershey Felder and Trevor Hay’s sleek scenic design; costumer Melissa Bruning’s expert 1950s shirtwaist dresses).

The good news is that the score of Prima-Smith tunes (played with period precision by the seven-piece band under Paul Litteral’s musical direction) packs just as effective an emotional punch. Stewart is a magnificent Keely, a vocal powerhouse easily on a par with Smith, and her skillful underplaying perfectly complements Crivello’s mesmerizing manic intensity. It’s a chemistry whose sheer seductiveness is only fully revealed in a dramatic finale, when their celebratory duets on “Old Black Magic” and the signature medley “Just a Gigolo”/”I Ain't Got Nobody” are repeated as somber solos and become transformed into surprisingly heart-wrenching songs of regret and separation.

Gil Cates Theater at the Geffen Playhouse, 10886 Le Conte Ave., Westwood; through Jan. 17. (310) 208.5454, geffenplayhouse.com.