Over the course of more than 60 years in show business, Sammy Davis Jr. (1925-1990) went from 4-year-old vaudevillian to the Kennedy Center Honors because he always knew he could. He overcame the loss of an eye and racism along the way, trailblazing for others who came along afterwards. Without becoming maudlin over the entertainer’s tragic death from throat cancer or overemphasizing his lifelong excesses in clothes, women, cigarettes and booze, Leslie Bricusse’s musical tribute, “Sammy” (playing at the Old Globe Theatre in its world premiere through Nov. 8) presents the story in most affecting fashion, even before one learns that in Davis’ first film role, at 8, he played a small African-American boy who dreams of becoming president. Bricusse also resists the temptation to become a character in his own book; instead he frames the entertainer in an economical pastiche of his life in dance and song. Tony Award nominee Obba Babatundé, who claims Davis as his mentor, portrays Sammy. A grand performer, Babatundé is small of stature and girth, as Davis was. He is an apt portrayer of Davis, who is said never to have been still. Rife with characters, movement, 23 musical numbers (some by Bricusse and others by Bricusse and Anthony Newley) and a lively 13-piece orchestra conducted by Ian Fraser, “Sammy” seldom rests either. If one felt exhausted at the end of the show on opening night, Oct. 2, imagine the toll on Babatundé, who appears vocally and physically indefatigable. It’s an amazing challenge fully met, and one must admit there are moments of repose within songs, places where Babatundé sings quietly and even more beautifully, but he is still singing. Other characters include Sammy’s grandmother (Ann Duquesnay), his father (Ted Louis Levy), Will Mastin (Lance Roberts) Eddie Cantor (Perry Ojeda), Frank Sinatra (Adam James), Dean Martin (Troy Britton Johnson) and Sammy’s women, played by Mary Ann Hermansen, Heather Ayers, Victoria Platt and Keewa Nurullah. All this and an ensemble of topnotch singers/dancers, with choreography by Keith Young, direction by Keith Glover, orchestrations by Ned Paul Ginsburg and further conducting duties, music direction and dance music arrangements by Rahn Coleman. In addition to four songs from Bricusse and Newley’s “Stop the World — I Want to Get Off” (“What Kind of Fool Am I?,” “Gonna Build a Mountain,” “Once in a Lifetime” and “Someone Nice Like You”) the show also includes “The Candy Man” and “The Only Man for Me,” a trio for wife and mistresses. Babatundé and  Hermansen’s song and dance number, “Something in Your Smile,” fairly sizzles. Some might carp that the show suffers for lack of the Davis-recorded cover of Jerry Jeff Walker’s “Mr. Bojangles,” which he always included in his act. Some might even imagine, as this listener, that snatches of the tune are heard in the 11th-hour orchestration. Instead, the production ends with Bricusse’s tribute song, “The Greatest,” and then, more quietly, with Babatundé singing “The Good Things in Life” from Bricusse and Newley’s “The Good Old Bad Old Days.” There are a few too many “Ta Da!” moments in Act I, and the Act II drug scene seems over long, as if we don’t know what the Candy Man sells. Clocking in at 2 hours and 45 minutes “Sammy” is a bit flabby, but overall, the show is a wealth of entertainment and a fitting tribute to the amazing Sammy Davis Jr. “Sammy” continues at the Old Globe Theatre, Balboa Park, through Nov. 8 with performances at 7 p.m. Tuesdays, Wednesdays and Sundays; 8 p.m. Thursdays through Saturdays; and 2 p.m. Saturdays and Sundays. For tickets ($54-$89) and information, visit www.theoldglobe.org or call (619) 234-5623.