Who is the director of the episode "rain of terror" that was written by John Brown?
CREATE TABLE "table1_13740746_1" (
  "ep_no" real,
  "title" text,
  "director" text,
  "written_by" text,
  "original_air_date" text,
  "production_no" real
);
SELECT "director" FROM "table1_13740746_1" WHERE "written_by"='John Brown' AND "title"='\"Rain of Terror\"';