In the year 2961, the time is after humanity and nature has recovered the land. A hunter named Cygnus is called to rise above his duty. He provides for Last Arc, a once nomadic band of survivors in need of food and water that is now growing scarce. The answer must be found before a group of outlandish Heretics descend upon them. Cygnus must voyage across the treacherous landscape to defend his people. Sent by Nova, the matriarch of the band, she acts based on her vision for Cygnus to find a seed of hope. The future of Last Arc is for him to discover, Cygnus ventures into a hostile landscape in search of an answer for his people. On this journey of encountering many traps and dangers, Cygnus discovers what has been hunting him is his identity.

小儿麻痹症在里约热内卢爆发，血清在圣地亚哥，只有一种方法可以让勇敢的飞行员冒着危险的天气和安第斯山脉险峻的山峰将药物送到急需的地方。在南美洲，令人畏惧的山脉和危险的天气阻碍了 20 世纪 30 年代跨安第斯欧洲航空邮件航空公司的运营。奥古斯特·佩勒林（罗伯特·蒙哥马利饰）负责在里约热内卢运送血清以阻止小儿麻痹症的爆发，他克服了恐惧，但却因迟到而受到 航空公司严厉的董事 A·里维埃（约翰·巴里摩尔饰）的斥责。里维埃尔决心让夜间飞行计划顺利进行，他派飞行员朱尔斯·法比安（克拉克·盖博饰）和他的无线电操作员进行另一次危险的飞行。两人遭遇暴雨，当法比安夫人（海伦·海耶斯饰）来到总部时，她意识到她的丈夫迟到了。两名飞行员在海上盲目飞行时，燃料耗尽，选择跳伞，但却溺水身亡。里维埃拒绝辞职，并命令一名巴西飞行员（威廉·加根饰）将邮件送往里约，但飞行员的妻子（玛娜·洛伊饰））恳求他不要去。尽管存在危险，夜间邮件仍按时送达。飞行员感到绝望，他的航班只意味着巴黎的某人可以在周二而不是周四收到明信片，但当血清也被运送并拯救了一个孩子时，它的真正价值就得到了证明。母亲在孩子的床边高兴地哭泣，场景消失在海上漂浮着两个降落伞。一架幽灵般的飞机出现了，法比安微笑着坐在控制台上。他飞向天空，身后跟着一群幽灵双翼飞机；屏幕上出现以下文字：“这就是人类的勇气……人类死去……以便其他人可以生存……因此，人类的帝国最终可能会凯旋而上！”小儿麻痹症在里约热内卢爆发，血清在圣地亚哥，只有一种方法可以将药物送到急需的地方：由勇敢的飞行员冒着危险的天气和安第斯山脉险峻山峰的风险飞来。

　　A charming and very daring thief known as Arsene Lupin is terrorizing the wealthy of Paris, he even goes so far as to threaten the Mona Lisa. But the police, led by the great Guerchard, think they know Arsene Lupin's identity, and they have a secret weapon to catch him.