Opposite Emily Blunt, who assumes the role of the magical Banks family nanny that Julie Andrews won an Oscar for, Miranda plays a lamplighter, or leerie, named Jack, a character not found in P.L. Travers’ writings but derivative of Bert, the charming chimney sweep Dick Van Dyke played in the original film. The new role was the brainchild of Marshall and his producer, choreographer and partner John DeLuca.
Source: latimes.com – Los Angeles Times