Table: tv_episode_data_68
Columns: episode
title
directed_by
written_by
originalairdate
viewing_figures_millions_sourced_by_barb_includes_itv1_hd_and_itv1_1

Question: What is the episode number for "case two (part 1)"?
SQL: SELECT "episode" FROM tv_episode_data_68 WHERE "title" = '"Case Two (Part 1)"'

Question: What is the original air date for the episode viewed by 7.12 million?
SQL: SELECT "originalairdate" FROM tv_episode_data_68 WHERE "viewing_figures_millions_sourced_by_barb_includes_itv1_hd_and_itv1_1" = '7.12'

Question: Who directed the episode viewed by 7.35 million?
SQL: SELECT "directed_by" FROM tv_episode_data_68 WHERE "viewing_figures_millions_sourced_by_barb_includes_itv1_hd_and_itv1_1" = '7.35'