CREATE TABLE table_20912 ("No. in series" TEXT, "No. in season" TEXT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original airdate" TEXT, "Production code" TEXT)

Who directed episode 12 in season 3?
SELECT "Directed by" FROM table_20912 WHERE "No. in season" = '12'
SELECT "Directed by" FROM "table_20912" WHERE "No. in season" = '12'