HAD HITLER'S ARMY landed in Boston Harbor Friday night, it could hardly have been more devastating than the performance Patti Labelle, Nona Hendryx and Sarah Dash, otherwise knowns as "Labelle," dropped on downtown Boston's Orpheum Theater that evening. Voluminous plumes, vibrant booties and large doses of pure, rock-bottomed funk held the packed house spellbound for a solid two hours.

Three fine vocalists, the group descends from Patti Labelle and the Blubelles, the also-sang soul trio that followed in the wake of the Supremes during the mid-sixties. Since their return from Europe little more than a year ago, the group has developed a totally new act and a sound destined to sway the record charts for quite a while.

The costumes worn by the three women were awesome, bizarre to the extent that one wonders what manner of being could create such trappings. During the first half of the performance the three ladies appeared in outfits of all silver, ranging from Patti's futuristic gown to Nona's space-like body suit, seemingly painted over her shapely figure.

The costumes the ladies wore during their second act, however, were truly marvels to behold. The spotlight found Nona on stage left with a black floor-length cape covering an enticingly sheer body-stocking with silver boots and silver plates, discreetly covering a minimal portion of her body. A huge white plume crowned her head. She and Sarah lifted their eyes upward as Patti Labelle appeared atop a 20-foot stairway in center stage, wearing a cape and train profusely ornamented with orange and black feathers, reiterating the program's theme and title of the group's latest LP recording with Epic, "Nightbirds."

The show was good, too good--almost to the point of being decadent. Their sexful vocal arrangements and provocative lyrics ("I come like the pouring rain each time you call my name") was fast to send an almost orgiastic fervor throughout the audience. The atmosphere at times recalled images of the bawdy cabarets of the Weimar Republic when the Nazis were coming to power or of Times Square on any given Saturday night.

Labelle had a large, almost cult-like following there from as far as New York and Philadelphia, as numerous intermission-time re-encounters revealed. And indeed some of the members of this group were almost as entertaining as the performance, looking like personalities from a "Who's Who in Wonderland" directory. Glitter in the jammed lobby reached from wall to wall, a la East Village via Hollywood chic.

The evening, although risque for some, provided excellent entertainment for all. See Labelle. You won't regret it.