Isaac Florentine’s direct-to-video film Ninja (2009) introduced the character of Casey Bowman (Scott Adkins), an American orphan raised in a martial arts dojo in Japan, who is tasked with protecting an armoured chest of ancient weapons in New York. Ostensibly a sequel, Ninja: Shadow of a Tear is set in Japan, Thailand and the jungles of Myanmar, and only retains Casey and his love interest Namiko (Mika Hijii) from the first film. These obvious differences mean that the sequel can absolutely be watched as a separate entity…