The saga of the Houlihan's restaurant chain, which brings Washingtonians one version of the eatery in the Georgetown Park shopping mall, is the tale of a small-time, small-town business gone conglomerate.

The story begins in the early 1960s in Kansas City, Mo., when restaurateurs Joseph and Bill Gilbert and Paul Robinson opened a food establishment called Plaza III on the stylish Country Club Plaza there. The success of that enterprise led the partners to branch out across the city, opening a complex of several restaurants atop a local skyscraper and gaining control of the food concession at the Kansas City airport.

Success in the Midwest suggested expansion outside of it, so Gilbert/Robinson Inc. opened The Leather Bottle restaurants in St. Louis, Little Rock, Ark., and Atlanta. Other restaurant services came in between and, in 1971, the first Houlihan's was born in Kansas City, a prosperous locale that was gradually being peppered by other Gilbert/Robinson creations, including Sam Wilson's Meat Market and Annie's Santa Fe, which have developed into chains alongside Houlihan's.

In 1978, Gilbert/Robinson Inc. was able to acquire additional financial support by merging with the Fortune 500 conglomerate W. R. Grace & Co. Gilbert/Robinson Inc. now has 62 restaurants, including 44 Houlihan's, and the concern hopes to open eight or nine new businesses in 1982. Total sales for 1980 were $86 million and, for 1981, $113 million.

But Houlihan's, as exemplified by the new Georgetown Park location and by the first local Houlihan's in Bethesda, retains a distinctive Midwestern character, with a menu replete with entres such as "Banana Cabana," "Bourbon Street Breakfast" and "Nouvelle Burgers."

Paul Robinson, now vice president of corporate and interior design, says he and his wife Edna personally supervise the decoration, and the many Houlihan's are all somewhat similar, cluttered with turn-of-the-century advertisements, Humphrey Bogart posters and Victorian bric-a-brac.

"My wife and I do most of the buying," said Robinson. "We have 15 buyers in London and a buyer out in California. We also have a huge, 80,000-square-foot warehouse in Kansas City where we store $1.5 million worth of inventory, and our own moving van."

One characteristic of Gilbert/Robinson Inc. that has remained from the days when it was a small-scale business is the company's resistance to franchising. All restaurant managers and chefs are trained by the company at schools in Kansas City.

"We don't franchise anything," Robinson said. "We just don't believe you can control the quality in a franchise. All 62 of our restaurants are company-operated."

The Houlihan's restaurant in Georgetown will open on Jan. 21.