At Keiun's urging, Koyou arrives in Plum village, which is being ravaged by a mysterious illness. Unable to figure out the disease's origin or a proper treatment though, the young genius doctor is truly stumped! Could the answer be something simple that's been staring her in the face? Or has Koyou finally met her match? Meanwhile, the Divine Voice's past identity comes to light in the thrilling conclusion to this arc!