The documentary "Soyuz-Apollo. The Force of Gravity" is dedicated to the history of the legendary "handshake in space" – the docking in near-Earth orbit of the Soviet and American spacecraft Soyuz-19 and Apollo in 1975. The event took place at the height of the Cold War between the USSR and the USA. The unique international project was an important step of the two nuclear powers towards each other, and the friendly handshake of the crew captains Alexei Leonov and Thomas Stafford in space inspired hope for a warming of the political climate on Earth. The film uses documentary newsreel footage and memoirs of participants in those historical events: pilot-cosmonaut of the USSR and the Russian Federation, twice Hero of the Soviet Union, Aviation Major General Alexei Arkhipovich Leonov and Aviation Lieutenant General, test pilot, NASA astronaut Thomas Patten Stafford.