The film is set in 1965, during the Cold War and the Space Race between Soviet Union and the United States. The Soviets plan to send a man into space. During the construction of the craft, a technician is killed and the engineers question the safety of the craft. Evgeny Mironov (Alexei Leonov) and Konstantin Khabensky (Pavel Belyayev) are called to man the craft, but during a skydive Pavel injures his leg landing and is considered unfit. He is replaced by Yevgeny Khrunov, much to Alexei's dismay. Fueled by anger and determination, Pavel recovers through training and eventually is re-admitted, delighting Alexei. The Voskhod 2 launches, and Alexei makes a spacewalk. It is initially successful but ends in disaster when the ship loses communication with ground control and Alexei passes out.