Now this is what City Center's Encores! series should always be: A-list Broadway talent tackling challenging shows with must-hear scores. For the eagerly awaited April concert staging of Stephen Sondheim's little-seen Anyone Can Whistle , director Casey Nicholaw has landed three above-the-title favorites--Sutton Foster, Raul Esparza and Donna Murphy--making this one-week concert the starriest show in town! The wacky 1964 musical comedy (which only ran for 9 performances on Broadway) concerns a desperate town run by a corrupt mayor (Murphy) which gets turned on its side by the arrival of a myserious doctor (Esparza), who falls for an idealistic nurse (Foster). The cast welcomed Broadway.com to a rehearsal at City Center on March 30, at which Foster sang the gorgeous title song and Murphy kicked up her heels with the kicky "Me and My Town."