A 300-year-old book is discovered which chronicles the adventures of the legendary Samurai Troopers... centuries before they happen! But what does this mean? Are the Troopers merely puppets in some cosmic play, acting out parts? Who is this mysterious Suzunagi, a mysterious girl who entices each of the warriors with their hearts' desire - salvation, new armors, freedom from a life of fighting. Why is she so interested in the troopers and their armors?

力そのものが具現化した「輝皇帝の鎧」。しかしそれはひとつだけではなかった。真夏の新宿を襲う謎の異常気象。それと共に現れた褐色の戦士ムカラ。彼は黒い輝煌帝となって、恐るべき力でサムライトルーパーたちを撃退。遼と征士をタンザニアに連れ去ってしまう。