Oh Sun-hee, the greatest star from Wando, files for divorce after a long-standing conflict with her husband, Kang Sung-gi, and heads to her hometown, Wando, to escape the noisy media. Initially planning to visit her parents' graves and then return to Seoul, she is drawn back to Wando by a familiar restaurant sign. There, she unexpectedly reunites with friends from her childhood.

In the dead of night, a body donated for organ transplants mysteriously disintegrates into ashes. Soon after, five recipients, given a heart, corneas, lungs, liver, and kidneys, begin to develop supernatural powers. A teenage girl gains immense strength, a hipster manipulates electromagnetic waves, a novelist summons powerful gusts, a factory manager can heal others, and a woman discovers a strange, still-unidentified ability. Together, they form a reluctant but heroic team known as "HI-FIVE." But they aren't the only ones transformed. A cult leader who received the donor’s pancreas gains the terrifying power to drain life energy and sets his sights on stealing the abilities of HI-FIVE to achieve godlike domination.