The premise of this show is simple. Well, at least by Fringe standards. Follow along: Frank Sinatra and Dean Martin are stuck in purgatory after living debauched, misogynist lives. God — a female with a wicked sense of humor — sentences them to afterlives as women, to fully comprehend the damage they caused during their playboy wake. “God didn’t like the way we treated the broads,” they explain.The iconic entertainers become Frank Shenatra (Donna Kay Yarborough) and Dame Martin (Sadie Bowman) and showcase their undead lounge act to an attentive and game crowd (or jury) at the Coffee Emporium. By show’s end, if they have learned their lesson and grown as humans, they get an express pass to the pearly gates.The verdict? Well, buy a ticket if you want to know the ending. Let’s just say if I were the jury, I’d be hung. There is so much good and fresh about SHEnatra. But it’s ultimately uneven.The show fills the side room at the Coffee Emporium, and on opening night, it was a packed, attentive crowd. That will happen when you return to the Fringe after the pair’s Famous Haydell Sisters Comeback Tour was a big hit in the 2015 Fringe.Yarborough and Bowman fed on the energy. Much like their characters, they stopped and chatted with audience members, interacted and played jokes in true vaudeville style.The opening number, set to “Come Fly with Me,” created the tone for the evening. All the tunes are familiar hits, with switched-up, turned-on-their-ear lyrics to hammer home the gender bend and afterlife themes.And therein lies the show’s most charming asset and its most challenging liability. The whole shebang is based on the cleverness of the tweaked lyrics. While some songs knock ’em out of the park, others are weak dribblers.The witty takes on “Tender Trap,” “Witchcraft” and “That’s Amore” land in the former camp. Hysterically funny, they had the audience giggling with delight. No lyric spoilers here: Just enjoy them and thank us later.But mixed in to the hour-long set were some stinkers, including “Fly Me to the Moon,” which is now about hunger pangs, and “You Belong to Me,” which is now about facial hair.As performers, Yarborough and Bowman are game for the show’s conceit. They strut the stage with all the confidence of their alter egos and, in places, they sing damn well. The duet to the tune of “Something Stupid” particularly showcased their vocal chops. Credit must also be given to pianist Nate Butler, who keeps the numbers swinging.It’s a shame that some of the numbers are such lyrical let-downs. One wonders — hopes, even — that the show can be workshopped and refined further so that all the numbers land effectively. Because when they do, SHEnatra is wow-ee-wow-wow.