What country has a series premier of unknown and mbc action as their TV network?
CREATE TABLE "international_broadcasts" (
  "country" text,
  "tv_network_s" text,
  "series_premiere" text,
  "weekly_schedule" text,
  "status" text
);
SELECT "country" FROM "international_broadcasts" WHERE "series_premiere"='unknown' AND "tv_network_s"='mbc action';