CREATE TABLE table_17467147_1 (directed_by VARCHAR, us_viewers__million_ VARCHAR)

When there are 12.70 million u.s. viewers who is the director?
SELECT directed_by FROM table_17467147_1 WHERE us_viewers__million_ = "12.70"
SELECT "directed_by" FROM "table_17467147_1" WHERE "12.70" = "us_viewers__million_"