The Day the Ocean Disappeared — Lisbon, 1755

Lisbon, 1755: an earthquake, a retreating sea, a devastating tsunami—and the warning hidden in that bizarre sight.

On the morning of November 1, 1755, a great earthquake struck under the Atlantic southwest of Portugal. Then a tsunami reached the Tagus. Then fires spread through the city for days. This film follows that chain of events from the waterfront and explains the physics: why the sea can pull back first, and why it does not always do so. A clearly labelled hypothetical chapter then asks what the same warning means for a coastal city today.

Chapters
00:00 The Water Is Gone
00:46 A City Before the Shock
02:02 The Ground Moves
03:15 Why the Sea Can Retreat
04:30 The Water Returns
06:00 What If It Happened Now? (hypothetical scenario)
07:30 The Signal in an Empty Harbor

Visuals are AI reconstructions, not archival footage. The dockside witness is fictional; Chapter 6 is a hypothetical scenario, not a prediction. Narration by Eli · Time & Space. Sources are in the pinned comment.

If you are on a coast and feel strong or long shaking, or see the sea suddenly pull back, move to high ground or inland and follow local emergency advice. Do not wait for an official warning.