Mar adentro
After Amenábar completed "The Sea Inside" (2004), he took a break and traveled to the island of Malta, where he used his free time to explore the night sky. Seeing the Milky Way galaxy, Amenábar began to discuss astronomy with his friends, speculating about extraterrestrial life on other planets. He started to research astronomy and came across "", by American astronomer Carl Sagan. Amenábar also studied historical figures such as Ptolemy, Copernicus, Johannes Kepler and Galileo, but found himself most interested in the story of Hypatia, a 4th-century Greek astronomer whose history, he felt, was still relevant in the 21st century: "We realized that this particular time in the world had a lot of connections with our contemporary reality. Then the project became really, really intriguing, because we realized that we could make a movie about the past while actually making a movie about the present."