Yong-nam was one of the best rock climbers in college but hasn't had much luck elsewhere after graduation. He has failed to get a job since graduating and has to rely on his parents just to get by. He's a deadbeat living with his parents and doesn't see much hope for the future, he can't even land a date.
For his mother's 70th birthday, he insists on hosting a party at a roof top garden restaurant, where his old crush, Eui-ju works. When a disaster strikes, covering an entire district in Seoul with mysterious white gas, he has to use all of his rock-climbing skills with the help of Eui-ju to get everyone to safety.
What his mom once thought to be a useless skill soon turns out to be the group's only hope for survival.