Keanu Reeves makes his (possible) final outing in John Wick: Chapter 4 (Picture: Lionsgate)

‘Not even you can kill everyone,’ Hiroyuki Sanada tells his old friend John Wick (Keanu Reeves). 

Challenge accepted. Because even by John Wick’s own, extreme standards, the body count is off the scale, in this fourth and, seemingly, final instalment of the loony toony, shoot-em-up franchise that takes fight action to a whole new level.