28岁的小青年青山胜人(长濑智也 饰)从未想到自己的人生会如此短暂,在此之前他终日浑浑噩噩,胸无志向,然而一直诊断书却令他遭受了前所未有的打击。他的脑部长了肿瘤,命不久矣。入院期间,胜人结识了只有14的女孩白石春海(福田麻由子 饰)。春海自幼患有绝症,从7岁至今所有的日子都在医院中度过,而她的生命也慢慢走向终点。胜人和春海同病相怜,成了一对忘年交。某晚,他们偷偷进入医院厨房喝酒,胜人兴之所致,决定带从未看过大海的春海前往海边。 两人走出医院,驾着K3企业社长小久保(长冢圭史 饰)的豪华跑车绝尘而去,阴差阳错他们又成了持枪抢劫的匪徒。警方和K3的人在身后紧追不舍,胜人和春海则朝着梦幻般的大海持续前进……"Heaven's Door" starts off with rugged Katsuhito Aoyama (Tomoya Nagase) getting canned from his job as a car mechanic. While leaving work, he suffers from a migraine that causes him to nearly pass out. Katsuhito then visits the hospital to receive some ultra-heavy news: the cause of his migraines is an inoperable brain tumor the size of a human fist that will likely take his life in the next couple of days. During Katsuhito's first night at the hospital he meets a spunky girl young named Harumi Shiraishi (Mayuko Fukuda), who steals his cigarettes. Harumi is also a terminally ill patient suffering from cancer. Later that evening, the two sneak down into the cafeteria area and drink lots of tequila together. While in a drunken haze, Katsuhito decides to take Harumi out of the hospital and to see the ocean for the first time in her life. When the pair walk out of the hospital they spot an expensive import car with its doors unlocked. What Katsuhito and Harumi are unaware of is that the ...