Image courtesy of www.henshinhalloffame.com/lionmaru/
Kaiketsu Lion Maru, or literally translated as Swift Hero Lion Maru, was a tokusatsu series that aired from April 1, 1972 to April 2, 1973 for 54 episodes.
Like Henshin Ninja Arashi, Kaiketsu Lion Maru is set in feudal Japan. In the late-1500s, three orphans, Shishimaru, Saori, and Kosuke go around defending people from Akuma Gosun (Devil Gosun).
Shishimaru carries two swords, an ordinary one used in combat and another which transforms him into Lion Maru. This sword is locked in its sheath and will only be removed when Shishimaru recites the words "Kaze O! Hikari O! Ninpô Shishi-Hengen!" ("Wind, Light, Ninja Skill, Lion-Transform!"). After slashing the monster-of-the-week with this sword, he runs his hand down the back of it, and in doing this he causes the monster to explode. Once he puts the sword bak in its sheath, he changes back to Shishimaru.
Saori is quite capable in combat as well, as she is often able to fight two handed with her sword and a sword taken from the enemy. Kosuke can play his flute to summon a pegasus named Hikarimaru. He also uses a portion of his supply of black powder to produce small bombs. Hikarimaru is often ridden by Shishimaru or Lion Maru.
The leader of Akuma Gosun takes a human second-in-command, Jonosuke, who, with a magical sword of his own, can transform into Tiger Jo, a tiger equivalent of Lion Maru. Jonosuke was initally played by Kozi Tonohiro, but after he died in an accident, Yoshitaka Fukushima took over the role for the rest of the series run.
Image courtesy of www.henshinhalloffame.com/lionmaru/tj.htm
The series was followed by a similar series titled Fuun Lion Maru, which featured a similar plot and characters, but whose story is not connected to this series.
Here's the theme song: