Review: “Rihanna/Ke$ha”

When she first emerged on the scene, Rihanna was the very embodiment of sweetness and light, a purveyor of airy pop all but untouched by real world troubles. Times, to understate things, have changed for the Barbadian singer, who has traded the bubblegum for barbed wire – and the gentle island breeze for hurricane force gales.

On this, the Gotham stop on her first large-scale trek across North America – dubbed “The Last Girl On Earth” tour – Rihanna surrounded herself with props, including a hot pink tank and a trashed car that she sledge-hammered, a la punk pioneer Wendy O. Williams. Unfortunately, she spent far more time on the trappings than the arrangements of the songs delivered, which ranged from the blithely catchy {“Rude Boy”) to the dishearteningly leaden (“Rehab”).

Drawing heavily on her new “Rated R” album, a set piece of sorts about bad romantic vibes inspired by her disastrous relationship with fellow singer Chris Brown, the perf cast Rihanna as a sort of avenging angel capable of conveying unhinged anger (on “Disturbia”) and worrisome anxiety (on a careening version of “Russian Roulette”).

Ultimately, the 22-year-old was hampered by her utter lack of emotional depth as a vocalist. She hit her mark time after time traversing the post-apocalyptic staging – which bodes well for her impending big-screen turn in the board-game adaptation “Battleship” – but in the end, the snarl of “Breakin’ Dishes” and the giggle of “Umbrella” were all but indistinguishable.

Ke$ha opened the proceedings with a peripatetic set that put a post-modern take on the pop perfs that peppered network variety shows a generation or two back. Flitting from style to style like Cher on steroids, she took on frothy Euro-pop and feather-light hip-hop – even strapping on a guitar for some old-school hair-metal, Ke$ha dealt out a series of vignettes that were clearly Xeroxed, but somehow cartoonishly vivid enough to captivate.