A group of friends finds themselves stranded in an old hotel in Thailand. As they uncover the history beneath the walls, they're slowly drawn into its sinister past, making it even harder to get out alive.

Kline, a former Los Angeles police officer turned private detective, is hired by a powerful pharmaceutical conglomerate boss to investigate in Asia the disappearance of his only son, Shitao, whom he has not seen in person since the boy was ten. Now in his 30s, Shitao has gone missing in the Philippines where he had been helping in an orphanage.

A team of Interpol agents arrive in the city to testify against a local crime lord. However on the way to court the vehicle carrying the Triad boss is attacked and the crime lord snatched, not by his own people but by another foe.

In the time of the Qing Dynasty, the Emperor Yongzheng created a secret army known as the Guillotines. It was the job of the Guillotines to protect the Emperor by killing anyone who posed a threat to him or his rule. After 348 successful missions to eliminate their target, the 349th assignment proves to be their last.