There is a vicarious thrill in watching improvisational performances. The risks taken by the performers who are armed only with imagination and wit allow the audience to partake in the delights of impromptu discoveries that usually occur only in the isolation of the studio. When all is clicking, it is marvelous.

It was marvelous last night at the University of Maryland Studio Theatre, where Improvisations Unlimited presented a program of improvisational sets and rehearsed dances. Modeled loosely on Grand Union, the seminal improvisational group of the '60s, Improvisations Unlimited is a little gem of a company whose approach is based on a delight in individual differences in problem-solving and interpretation. The company members are young, fresh and slightly unfinished, the qualities which allow for their fredom of imagination. In last night's performance, the emphasis was upon humor: "Sure is tough when you have to shake and schlep at the same time -- not to mention singing," wailed one dancer as she shimmied while hanging upside down.

"Dreamcatchers," a work created for the company by New York choreographer Kei Takei, is a ceremony which suggests how the fantasy of children's games and rituals prepare a child for many realities of the adult world. The central allegory of "Dreamcatchers" is the maturation of a young girl with the aid and reassurance of an older woman who coaxes her into the inevitable.

Meriam Rosen's "Three Times" is a lighthearted look at how time affects the perception of events. Filmic techniques of slow motion and stop action are adapted for movement exploration. In extreme slow motion, a simple fall becomes microscopically fraught with pain, horror and unutterable surprise at the sudden loss of support.

The program will be repeated tonight, tomorrow and Saturday at 8 and on Sunday at 2.