"Many areas of London might be under water for days. For example, the Isle of Dogs could be under eight feet of water for six days. River engineers believe that it is not a matter of if there is a flood, but when the flood comes." (Greater London Council)
Martin Ellis (Alan Dobie) is a blocked screenwriter who invites Helen, an actress (Kika Markham), to a hotel in central London to discuss an idea for a play he is writing with her in mind. As they discuss the play, Martin discovers that a businessman and an escort named Carol are sat at a nearby table and appear to be speaking lines from the as yet unwritten piece. Martin becomes anxious at what will eventually become of the girl, already knowing that the play will not have a happy resolution
Following a series of bomb attacks in London, a group of terrorists seize Britain's ambassador to Scandinavia. With the ambassador now a hostage in his residence, another group hijacks an airliner at the capital's airport, announcing that the passengers will not be freed until their demands are met. Colonel Nils Tahlvik, Scandinavia's resourceful and ruthless head of security, seeks to take an uncompromising stance against the terrorists yet his attempts meet resistance from unknown forces at every turn...