 In the 1960s and '70s, Wheeler achieved success as a playwright and librettist, and his output as Quentin Patrick slowed and then ceased altogether after 1965.However, Wheeler did write the book for the 1979 musical "Sweeney Todd" about a fictional London mass murderer, showing he had not altogether abandoned the genre.The early Q. Patrick detective stories generally follow the Golden Age "whodunit" conventions, with elaborate puzzle mysteries reminiscent of Agatha Christie or John Dickson Carr.