In 1943, the brilliant Leonard Bernstein (Cooper) becomes an overnight star at 25 filling in for the conductor of the New York Philharmonic who’s fallen ill. A dizzying career- and life- follow, with the flamboyant Bernstein scoring as composer and conductor, becoming the most famous name in his field. Early on, the clearly gay Lenny falls for actress Felicia Montealegre (Mulligan), and they marry. “Maestro” tracks the assorted ups-and-downs of their nearly three-decade union, focusing on the price of outsize fame, and Lenny’s inability to stay faithful to the woman he truly loves.

Most everything clicks in Cooper’s highly ambitious biopic, with the director/star’s uncanny transformation into this legendary figure front and center (the make-up, including a prosthetic nose, is fabulous); Cooper’s mastery of Bernstein’s voice and mannerisms completes the effect. Mulligan matches him as Felicia, whose love and admiration for her wildly gifted spouse is tempered with hurt over his oblivious self-absorption and repeated infidelities with men. Miraculously, at just over two hours Cooper’s depiction of one incredibly eventful life never feels overstuffed. Period details are note-perfect, and the score, consisting mostly of Bernstein’s own work, add to the film’s impact. This “Maestro” earns a standing ovation.