Handling of Super Sentai Cast Changes
I was inspired by Mr. Smith's entry on the Power Rangers side. This is mine:
Goranger- Since the late Baku Hakateyama was acting in a play so they for thirteen episodes got a different actor named Jiro Daruma to play Daigorou Kumano the substitute. In order to make way for Baku Hakateyama's return, Jiro Daruma's character was killed off in a rather dramatic episode when Can Opener Monster hit him at the stomach with a big blade.
Battle Fever J- First we have Diane Martin (who used her real name as the fictional character Diane Martin) left for some unknown reasons so she got her replacement Naomi Hagi to replace her as the pink ranger of the show. It was in episode 24 that the character was wounded by Dracula Monster and left the team alive rather than dead, a situation similar in B-Fighter when the female warrior was replaced by another female warrior. I personally thought that Kimberly Hart's departure was more well-handled than Diane Martin's. Later Yukio Ito who played the character of Kensaku Shiraishi got married during that time (episode 33) according to the sources, they had to kill him off. The replacement actor Naoya Ban (who played Jin Makoto) was introduced during that episode that Kensaku Shiraishi would die a rather dramatic death, being shot by Egos soldiers.
Sun Vulcan- Concerning the red ranger replacement, it was said that Ryuusuke Kawasaki left the set to pursue a better career, got Takayuki Hiba to replace him. In episode 23, it ended where they both shook hands before Ryuusuke Kawasaki left the show. It was a formal departure.
Bioman- Perhaps until today, the biggest mystery of today is to why Yuki Yajima left the set. Some say it had to do with pay roll issues, she had enough and quit Japan Action Club. Some say she was pregnant on set or other rumors says she was fired. We don't know. It was really quite forced because the actress left. Since Yuki Yajima wasn't there to film Mika Koizumi's tragic death, they got a random voice actress and only the stuntman for the whole series showed up to play the dying part. Jun Yabuki was immediately introduced in the next episode as Mika Koizumi's replacement. This is the only one where the original and the replacement did not appear in one setting.
Gingaman- In episode 25, the first Bullblack died so Hyuuga, Ryouma's older brother (played by Teruaki Ogawa) who was thought to have died immediately took over that position. I pretty thought that this was a strength in the writing in Gingaman compared to the awesome Lost Galaxy season.
Shinkenger- I don't know if Kaoru Shiba's actress Runa Natsui counts because while she was temporarily their leader, the actor Tori Matsuzaka was still on set given a minor role until it was his time to return once more.