Question: Who directed episode 21?
SQL: SELECT "Directed by" FROM "1-23958944-5" WHERE "No. by season" = 21.0;

Question: What is the series number of the episode "Pandora"?
SQL: SELECT "No. by series" FROM "1-23958944-5" WHERE "Title" = '"Pandora"';

Question: What episode was watched by 10.81 million US viewers?
SQL: SELECT MIN("No. by season") FROM "1-23958944-5" WHERE "U.S. viewers (in millions)" = '10.81';

Question: How many episodes are titled "Cops & Robbers"?
SQL: SELECT COUNT("No. by season") FROM "1-23958944-5" WHERE "Title" = '"Cops & Robbers"';

Question: What episode is directed by Bryan Spicer and written by Terence Paul Winter?
SQL: SELECT "Title" FROM "1-23958944-5" WHERE "Directed by" = 'Bryan Spicer' AND "Written by" = 'Terence Paul Winter';