CREATE TABLE table_24254 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( millions ) " TEXT)

when was the premiere when a 3.3 millions of North American watched the episode whose writer was Rob Wright?
SELECT "Original air date" FROM table_24254 WHERE "U.S. viewers (millions)" = '3.3' AND "Written by" = 'Rob Wright'
SELECT "Original air date" FROM "table_24254" WHERE "U.S. viewers (millions)" = '3.3' AND "Written by" = 'Rob Wright'