user: Question: What is the time of the transmission on 28 December 2008 with a running time of 66 min 21 sec?
Columns: ['Date', 'Time', 'Channel', 'Running Time', 'Notes']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['19 March 2008', '21:00', 'BBC Four', '66 min 44 sec', 'Original release']
SQL:

assistant: SELECT "Time" FROM "Table" WHERE "Running Time" = '66 min 21 sec' AND "Date" = '28 December 2008';