Which actors first appeared in episode "Blink" 1, 2, 3?
CREATE TABLE "main_characters" (
  "character" text,
  "portrayed_by" text,
  "first_appearance" text,
  "last_appearance" text,
  "duration" text,
  "episodes" text
);
SELECT "portrayed_by" FROM "main_characters" WHERE "first_appearance"='\"Blink\" 1, 2, 3';