CREATE TABLE table_17897 ("Episode #" FLOAT, "Series #" FLOAT, "Title" TEXT, "Director" TEXT, "Writer" TEXT, "Original airdate" TEXT, "Viewers  ( in millions ) " TEXT)

Who directed the episode that had 6.04 million viewers?
SELECT "Director" FROM table_17897 WHERE "Viewers (in millions)" = '6.04'
SELECT "Director" FROM "table_17897" WHERE "Viewers (in millions)" = '6.04'