A mysterious letter addressed to Wu Xie's late grandfather Wu Lao Gou disrupted the retirement plan of the "Iron Triangle", i.e., Wu Xie, Zhang Qi Ling and Wang Pang Zi. The letter refers to a mysterious underground palace called "Comet" in Mongolia. So as to make up for the regret of his grandfather, Wu Xie decides to explore the Comet, only to get involved in an unimaginable adventure encountering treacherous Mongolian bandits, the countdown to escape, the invisible rules of the burial chamber and monstrous creature... Wu Xie and his sworn buddies have no choice but to thread their way through for survival...Watch drama online for free.