CREATE TABLE table_18712423_3 (series_episode INT, viewers__millions_ VARCHAR)

What is the show episode number of the episode that reached 1.215 millions views?
SELECT MIN(series_episode) FROM table_18712423_3 WHERE viewers__millions_ = "1.215"
SELECT MIN("series_episode") FROM "table_18712423_3" WHERE "1.215" = "viewers__millions_"