The life of 22-year-old Chinese student Lei Jie at the University of Glasgow is as ordinary as the flowing water of the Thames - attending classes, working part-time, and making video calls with his mother. The only secret is his mother Su Qing's biological father who has never been mentioned. Until one rainy night, an Italian man in a suit knocked on the door of his rental house, handed him a ring engraved with thorns, and told him that his biological father was Vincent Colletti, the mafia godfather who controlled the British underground order, and he was the only heir. The sudden change of identity draws Lei Jie into the whirlpool of power struggles and family feuds. On one side is the past that his mother has hidden for half his life, and on the other is the bloody world of the mafia. This international student, who has never even been in a fight, is forced to pick up a gun and put on a ring, and in the darkness of a foreign country, he searches for the truth about his biological father, his mother's difficulties, and his own way of survival.
