Hey, Isn't That. . . ?

Josefina Scaglione and Matt Cavenaugh in the new production of "West Side Story" at the National Theatre. (Joan Marcus)

Stephen Sondheim catching the latest revival of "West Side Story," for which he wrote the lyrics more than a half-century ago, at the National Theatre on Friday night. Sweater, casual slacks, good seats -- on the aisle, fifth row or thereabouts. But, oh, what a night to see it: At the start of the second act, as Officer Krupke is called out to harass the Jets, the theater's white emergency lights started flashing, and a fire alarm sent the entire audience out onto the street.