Time Out says
Marking the very highest point ever reached by the kung fu genre, Lau's masterpiece concerns an imperial prince (Liu) travelling incognito in South China who 'enslaves' the petty thief Ho (Wong) by wounding him with a poison to which he alone possesses the antidote. When the prince is summoned back to Beijing for an urgent meeting about the imperial succession, the thief has no choice but to tag along; there are daily traps and ambushes on the road because a rival wants the prince out of the way. The film lovingly exploits the ambiguity of the central relationship: does the prince pick up the thief because he lusts after his body, because he wants to improve him morally or simply because he needs a bodyguard? Working with two of his own most brilliant pupils, Lau constructs several of the genre's most intricately choreographed set-pieces: the 'disguised' fight conducted while examining priceless antiques is in the Gene Kelly class.