Astrophysics engineers John Flemming and Dennis Bridger carry out the final checks of the world’s largest radio telescope, built in England under the leadership of Professor Ernest Rainheart. The night before the ceremonial opening, during the telescope’s calibration, a radio broadcast was caught coming from the direction of the Andromeda Nebula. Because of Earth’s rotation over a day, the information can be received only in parts; however, after a few weeks, the transmission starts repeating. A few months later, the scientists finally manage to collect the fragments of the broadcast in full. After studying it, it becomes clear that the message consists of three parts: instructions for building a computing machine, a program for it, and the data it must process. All that remains is to secure funding from the ministry and begin building a machine capable of running the transmitted program…