Hugo 's novels as well as his plays have been a great source of inspiration for musicians , stirring them to create not only opera and ballet but musical theatre such as `` Notre-Dame de Paris '' and the ever-popular `` Les Misérables '' , London West End 's longest running musical .
Hugo 's novels as well as his plays have been a great source of inspiration for musicians , stirring them to create not only opera and ballet but musical theatre such as Notre-Dame de Paris and the ever-popular Les Misérables , London West End 's longest running musical .