Table: episode_details
Columns: ep_no
title
director
written_by
original_air_date
production_no

Question: Who is the director of the episode "rain of terror" that was written by John Brown?
SQL: SELECT "director" FROM episode_details WHERE "written_by" = 'John Brown' AND "title" = '"Rain of Terror"'

Question: What is the production number of "rain of terror"?
SQL: SELECT MIN("production_no") FROM episode_details WHERE "title" = '"Rain of Terror"'

Question: Who wrote the episode called "mercury falling"?
SQL: SELECT "written_by" FROM episode_details WHERE "title" = '"Mercury Falling"'