CREATE TABLE table_29135051_3 (episode INT, guest_s_ VARCHAR)

which episode did sarah millican and grayson perry appear in
SELECT MIN(episode) FROM table_29135051_3 WHERE guest_s_ = "Sarah Millican and Grayson Perry"
SELECT MIN("episode") FROM "table_29135051_3" WHERE "Sarah Millican and Grayson Perry" = "guest_s_"