Beyond being directly or indirectly significantly influential (it inspired Frank Miller's comics, which inspired plenty, including Teenage Mutants Ninja Turtles), the notion of an American movie adaptation of Kazuo Koike and Goseki Kojima's  classic samurai saga Lone Wolf and Cub has long floated around Hollywood.  Darren Aronofsky (The Wrestler, Black Swan)  was thought of as the Lone Wolf and Cub guy.  Now, Justin Lin (The Fast and the Furious: Tokyo Drift, Fast & Furious, Fast Five) seems to be the one taking the sword. 

The Hollywood Reporter recently did a run-down of what's on tap for Lin's newly created Barnstorm Pictures.  Among his plans, Lin also is developing Lone Wolf and Cub, an adaptation of the acclaimed epic samurai manga, with  Marissa McMahon, the burgeoning producer and daughter-in-law of WWE CEO Vince McMahon. The duo is in the midst of packaging the project.

Lone Wolf and Cub is the story of Ogami Itto, a former executioner for the shogun.  After being disgraced by Yagyu clan, he takes his infant son Daigoro and begins a career as an assassin for hire, meanwhile, putting a complex revenge plot into motion.

The after partial release by First Comics in 1987, the complete manga series was released in North America by Dark Horse. 

Media Blasters released the live action TV series adaptation, while AnimEigo released the movies, including their Shogun Assassin localized edits.