The anime depicts Chief Commander Lu Dahai and the vast number of shipbuilding workers strongly demanding the trial voyage of the ten-thousand-ton ocean-going freighter "Dongfang," which is equipped entirely with domestically produced parts. Chen Zongjie, a member of the Party Committee of the China Foreign Transportation Bureau and the leader at the time, believes that the quality of the domestically produced main engine and navigation instruments is subpar. He orders that they all be replaced with imported ones; otherwise, the trial voyage will not be permitted. 　　Lu Dahai and the workers wage a tenacious struggle against this decision, also combating erroneous ideologies. In the end, they not only successfully set a new record for the trial voyage but also rescued a distressed Taiwanese fishing boat.