When your hero is as spectacularly garbed as the titular lead is in Akai Kageboshi, you need everyone else he’s fighting to provide visual contrast. So in what is one of the most colorfully costumed ninja films of the 60’s, there are some downright dour grunts in the trenches.
Hanzo, in his unassuming grey, is actually the central pillar in all this colorful drama. Twenty years ago, he caught a female spy sneaking into the castle. Wrestling around, the two get so hot and bothered, they have to go at it right on the spot (and knowing how manly ninja are, the inevitable happens).
It leads to a life of loss and regret for him, single motherhood and revenge obsession for her, and a tormented young man raised without a father figure who thinks its normal to meet girls by sneaking into their rooms at night in a chain-mesh hood.
There are some excellent ninja-on-ninja fights throughout AK, and the battle in the cane fields is rather good. See a few scens for yourself in the trailer below: