Johnnie To's Three is the director's latest collaboration with his muse Louis Koo, and their first thriller since 2013's Drug War. While that film sped around mainland China, Three keeps its focus on the hospital where cackling, Bertrand Russell-quoting criminal mastermind Shun (Wallace Chung, also a War veteran) has been admitted with a bullet to his head. Shun refuses to receive the necessary treatment from neurosurgeon Dr. Tong (Zhao Wei), who's already having one of the worst professional days of her life after a botched surgery; this is so Shun can continue to taunt pursuing Inspector Chan (Koo), while buying time for his associates to continue doing crimes in the outside world and preparing his escape from the hospital. Three makes great cinematic use of its claustrophobic single location, and it's at its best when To ratchets up the tension, particularly as Tong and rather patriarchal Chan grow increasingly frustrated by their inability to outwit the Lecter-clever Shun. The time spent exploring the hospital ward pays off in the climactic (and sole) action scene, in which the film takes a 10 Cloverfield Lane-level left turn into CGI-heavy action schlock at odds with the rest of Three's tone. A standalone piece of violent madness it's not bad, but as To has proved elsewhere, he can do better.