It is set in the same location, but involves a different positronic robot - one of the few in Asimov's stories to have neither a serial number nor nickname.

The researchers at Hyper Base are ready to test the first hyperspace ship.

The ship fails to function as planned, and Susan Calvin persuades Gerald Black, an etherics engineer (who had also appeared in "Little Lost Robot"), to board the ship in order to locate the fault.

As Calvin suspects, Black finds that the fault lies with the robot, which, as a result of imprecise orders, has damaged the controls of the ship.

They realize that the precise and finite robot mind must be compensated for by human ingenuity.