The two fall in love behind the back of Yan-yan’s abusive father, but their happiness proves short-lived. Lok, whose mother has recently died, soon realises his girlfriend exists only in his own mind. The story proper takes place six months later, when Lok meets the actual woman he first saw: Yip Nam (also Choi) is a postgraduate student, privately desperate to become Lok’s psychological counsellor and take his unique case of erotomania as her research subject.

What transpires is a multilayered and deeply emotional tale of desire and yearning, as Lok and Nam – both damaged, vulnerable souls – navigate the taboo territory of the relationship to find solace in each other. While Nina Paw Hee-ching, as Nam’s thesis supervisor, and Poon Chan-leung, as her married lover and academic colleague, provide decent supporting turns, this film belongs to the leading duo, who bring their characters’ internal turmoil alive.

It takes a leap of faith on the audience’s part to buy into Lok’s mental condition – the film’s central conceit – but Lau, a stage and television actor making his feature film debut, more than earns our sympathy with his tortured portrayal. Choi, recently seen in the Taiwanese hit Detention , also nails her dual roles in her first Hong Kong film appearance. The subtle transformation of their characters alone calls for repeat viewings.