SELECT original_air_date FROM table_21313498_1 WHERE us_viewers__millions_ = "3.3" AND written_by = "Rob Wright"
Kapan pemutaran perdana ketika 3,3 juta orang Amerika Utara menonton episode yang penulisnya Rob Wright?
CREATE TABLE table_21313498_1 (original_air_date VARCHAR, us_viewers__millions_ VARCHAR, written_by VARCHAR)