CREATE TABLE table_18217753_1 (written_by VARCHAR, us_viewers__millions_ VARCHAR)

Who were the writers when there were 27.11 million viewers?
SELECT written_by FROM table_18217753_1 WHERE us_viewers__millions_ = "27.11"
SELECT "written_by" FROM "table_18217753_1" WHERE "27.11" = "us_viewers__millions_"