Emo rockers My Chemical Romance channel Dr. Jekyll and Mr. Hyde

What if a band famous for one thing decides to try something else? Sometimes the group changes its name. Think of U2 in 1995, issuing an album as the Passengers, or the Beatles adopting the guise of Sgt. Pepper's Lonely Hearts Club Band to open themselves up creatively.

My Chemical Romance did something similar with last year's "The Black Parade," piling an ambitiously wide array of musical styles (quiet piano interludes, boogie-rock grooves) atop its usual jackhammer drums and aggressive guitars. The album also tackled a weighty narrative (about a loved one's death from cancer) and provided the New Jersey pop-emo band with an alter ego.

That dual identity was taken to the hilt at WaMu Theater on Monday night. At first, singer Gerard Way announced the group's name as the Black Parade; they then played the album start to finish. After a pause marked by a closed and opened curtain, the band returned as My Chemical Romance, performing a half-dozen more songs, mostly hailing from the star-making 2004 album "Three Cheers For Sweet Revenge."

It was ingenious pacing, with the more musically involved and emotionally fraught Black Parade material leavened by the more straightforward wallop of the earlier stuff.

Both versions of the group were in cracking form. The Black Parade set featured the group in black-and-white outfits like the Sgt. Pepper uniforms gone Goth, with the five band members, plus a guest keyboardist, donning pancake makeup for further contrast. The songs were up to the visual drama: "Welcome to the Black Parade" rose from plinking piano to a military drum march, while "House of Wolves" rode a fierce stomp that owes a lot more to the Marshall Tucker Band than the emo bands MCR took early inspiration from.

Returning to the stage in black T-shirts and jeans, with Way donning a black leather jacket, the group shed its face-paint and keyboardist and laid into "I'm Not Okay (I Promise)," the band's first big hit. It set the tone for the less layered, more straightforward group of songs MCR finished with. Having taken us through a pained narrative, now we could have a good time. The new non-album track "Heaven Help Us" moved at a hammering pace, while another "Three Cheers" hit, "Helena," brought the show to a soaring finish.