Ambitious stage biography meets exceptional performance versatility in a showmanly encounter at the Entermedia Theater. ''Lennon'' was created by Bob Eaton for the Liverpool Everyman Theater. It celebrates the native son who first rose to fame as one of the legendary Beatles. His subsequent independent career ended tragically when he was murdered on Dec. 8, 1980, in New York. With some 50 songs, mostly by Lennon and Paul McCartney, the nine-member American cast recalls the ups and downs of a jaunty, working-class lad who became so inseparably identified with the musical beat of the turbulent 1960s.
The talented young performers at the Entermedia prove equally accomplished, whether as actors, vocalists, or instrumentalists. Among them, they play more than 30 roles and 13 instruments. Their facility is the more impressive for seeming so effortless. What might have seemed merely a stunt is integral to the style and purpose of ''Lennon.'' That purpose has been to create an entertainment in which Lennon's life story is constantly related to the music he helped create and performed.
After casually assembling, the cast introduces the evening with the quietly tender ''In My Life'' and then turns the calendar back to Lennon's early years. There are loving memories of the aunt who brought him up and more raucous recollections of schoolmates and teachers. Lennon's exploits as a talented but rebellious art student and the Beatles' German appearances are among the liveliest and sometimes most hilarious of the sketchy incidents.
As the scenes and songs succeed each other, ''Lennon'' moves forward to the growing fame of the group, with such highlights as their American debut on the Ed Sullivan show and the attendant Beatlemania that seized an adoring public. Important characters like manager Brian Epstein and actor Victor Spinetti move on and off the scene. The second act deals with the Beatles' breakup, Lennon's marriage to and creative partnership with Yoko Ono, their estrangement during his period of alcoholism, and the domestic serenity that followed their reconciliation.
''Lennon'' is a long show. Some of its parts pass the time without particularly enriching the whole. The steady counterpoint of biographical fragments and musical numbers occasionally creates an impression of clutter. Nevertheless, at the preview I attended, the audience clearly enjoyed the generous reprise of songs that did so much to create the musical sound of a decade.