All The Way is based on the stage play of the same name, which follows Johnson from the assassination of John F. Kennedy to his re-election.
Cranston, who played Johnson in the Broadway run, will continue the role that earned him a Tony Award. All The Way broke a box office record for most money earned in a single week for a straight play, according to Entertainment Weekly.
Mackie will not only play King, but will also help write the script. Steven Spielberg will be producing, and Jay Roach will be directing. Production on HBO's adaptation is expected to begin this fall.