Double Seven

(from ebookjapan):

A full-color blockbuster 10 years in the making. Tobiba was working as a sheriff in the rural spot of Ghost River Town in America. Normally, only one regular train stops there each week, but a special train with a "showtime car" makes a temporary stop. The train was operated by drug dealers, and eight people were shot to death in the train.

After being kicked out of the train by the FBI agent who was investigating the case, Tobiba secured a woman after a struggle with the gunman, and the case was thought to be closed, but a mysterious shadow looms over the sports car they are riding in.