Time-displaced astronauts relearn purpose in utopia
Sergei Kondratyev and Evgeny Slavin, crew of a starship launched a century earlier, return through relativistic time dilation to 22nd-century Earth. Nobody needs them and nothing is scarce, so they must find a reason to act in a society where survival and wages no longer drive anyone. Kondratyev eventually finds footing in the Ocean Guard, doing hands-on work that tends the planet's seas. The episode shows that outsiders to abundance have to relearn motivation as chosen vocation rather than necessity.
