Michael Rader is the new artistic director of the Cape Playhouse in Dennis. Leslie Gardner, vice president of the board of trustees for the Cape Cod Center for the Arts, which operates the Cape Playhouse, made the announcement Monday. Rader is currently the resident director for the national touring production of “A Christmas Story, the Musical,’’ managing a company of more than 60 actors, musicians, and crew. He’s also served as artistic director for Cirque du Soleil on the international tour of “Varekai.’’ In addition to the Cape Playhouse’s regular, six-play season, Rader will develop the children’s season as well as special events. Rader will be introduced at the Cape Playhouse’s 90th anniversary gala Sunday.