Petula Clark Performs at Feinstein's at Loews Regency Bright lights, big city. Youth and hope. A glittering wonderland of infinite possibility where "everything's waiting for you." That is a paradisiacal dream world of "Downtown," held out like a bauble in Petula Clark's signature hit that entered the charts in late 1964 and went to No. 1 early the next year. Petula Clark inspiring her audience to sing along at her opening-night performance on Tuesday at Feinstein's at Loews Regency. As she sang it at Tuesday's opening-night show of her engagement at Feinstein's at Loews Regency, it barely mattered that Ms. Clark, trim and agile, with frizzy silver-blond hair and a diminished voice, is now 79. The spirit of the song and its incandescent sense of expectation, similar to the Drifters" hits "On Broadway" and "Up on the Roof" from the same period, had the audience singing along. Ms. Clark mentioned that Tony Hatch, who wrote "Downtown," as well as many of her other hits, had considered giving it to the Drifters. No sooner had Ms. Clark finished the song than she remarked that in her recent visits to New York she had noticed the proliferation of drugstores around the city. And "Downtown" was recycled as a funny piece of special material in which "Downtown" became "Duane Reade," and the magical sights included pantyhose, lip balm and dental floss. In the mid-"60s Ms. Clark, already in her 30s, was a sympathetic older sister to the youth culture that would soon become the love generation. Songs like "Color My World," "A Sign of the Times" and "I Couldn't Live Without Your Love," all of which she sang accompanied by a functional quartet led by Grant Sturiale on piano, offered encouragement to future hippies. If she was a swinging Englander, she was a clean-cut gal, not a slinky kohl-eyed "bird" who might lead a boy to ruin. Her ebullient sense of humor prompted a "Hee-Haw"-style version of "My Love." Ms. Clark has a musical-theater résumé that includes "The Sound of Music," "Blood Brothers" and "Sunset Boulevard." If she lacked the vocal heft to push Norma Desmond's anthem "With One Look" through the roof, her reading was powerful in its dramatic focus. Not so for the Cole Porter standard "Miss Otis Regrets," the monologue of a haughty servant who conveys the "regrets" of a society lady who has been executed by a lynch mob after murdering her lover and who is "unable to lunch today." Ms. Clark is simply too nice and optimistic a person to explore its gallows humor. Petula Clark performs through Feb. 4 at Feinstein's at Loews Regency, 540 Park Avenue, at 61st Street; (212) 339-4095, feinsteinsattheregency.com.