On "Starburst Night" on Ker Planet, Lexi, a brilliant mechanical engineer from Earth's lower class, accidentally saves Driann, the Supreme Interstellar Commander, who is suffering from a sudden fatal rejection reaction. The two have a one-night stand amid the pink stardust. When Lexi flees in panic, she loses her roommate Mia's bracelet, leading Driann to mistake the vain Mia as his savior and gift her the Commander's token of identity.
Lexi is transferred to Driann's command unit due to her exceptional mechanical talents. To survive under Driann, who deeply despises subordinates who seek favoritism, Lexi desperately hides her true identity. The two engage in intense workplace tension throughout perilous interstellar missions and daily training. Meanwhile, Mia, the opportunistic roommate who stole credit for the rescue, colludes with military insiders to suppress Lexi by any means necessary, even fabricating a pregnancy to force Lexi to resign. It isn't until Lexi takes a fatal assassination bullet meant for Driann that the false savior's lies are completely shattered, and the Commander and his hardcore mechanical engineer finally find their way to each other.
