user: Question: What is the original air date of the episode directed by Terrence Nightingall?
Columns: ['Series #', 'Season #', 'Title', 'Directed by', 'Written by', 'Original air date']
Types: ['real', 'real', 'text', 'text', 'text', 'text']
Sample row: [268.0, 1.0, '" Bloodline "', 'Stephen Cragg', 'Joe Sachs and David Zabel', 'September21,2006']
SQL:

assistant: SELECT "Original air date" FROM "Table" WHERE "Directed by" = 'Terrence Nightingall';