From Entertainment Weekly:
And there’s your fashionable answer. It appears that the already-animated pop star will lose little in translation to cartoon, sporting a seafoam-and-white punky dress accented with a tiara and platform shoes. Behold the cool-as-ice queen!
In the episode, Lady Gaga (playing herself) stops her Gaga Express train in the depressed town of Springfield and tries to boost the spirits of Lisa, who has become a complete social outcast. Using the power of positive thinking and song, can Gaga teach Lisa – and everyone in Springfield — that individuality beats conformity? We must believe so!
By the way, there will be plenty more Gaga to gawk at: This is only one of 18 outfits that she’ll wear in the episode, which airs May 20 on Fox.