CREATE TABLE table_1686 ("Episode" TEXT, "First broadcast" TEXT, "Graemes guest" TEXT, "Jeremys guest" TEXT, "Votes  ( % ) " TEXT)

what is the number of the episode where maria mcerlane where gramer guest
SELECT "Episode" FROM table_1686 WHERE "Graemes guest" = 'Maria McErlane'
SELECT "Episode" FROM "table_1686" WHERE "Graemes guest" = 'Maria McErlane'