Chilworth Manor, near Guildford, England was used as the filming location for Adela Marchmont's house. It is a country house hotel and has been used for other productions, such as an episode of Foyle's War called The Funk Hole and the movie The Wedding Date (2005).
The US premiere of this episode was on December 17, 2006, on the Biography Channel. Several censored words were blanked out.
This episode was planned to air first on A&E in the US on December 11, 2005, but it was pulled from the schedule and did not appear. It was shown in the UK on April 2, 2006.
This episode is based on Agatha Christie's book Taken at the Flood (1948).
The title seems to allude to some words of Brutus in Shakespeare's Julius Caesar:
"There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune".
Even better, Agatha may have had in mind some less well-known lines of the poet Byron -
"There is a tide in the affairs of women
Which, taken at the flood, leads -
God knows where."