Masayuki Onoda, Akihiko Hirata’s Nephew

I’m writing this off-the-cuff because it’s information that I have just found out today, so excuse me if it’s not up to quality standards.

Masayuki Mitsuya, born Onoda, is the eldest son of Utako Mitsuya and Yoshiki Onoda. He is not mentioned by name on Onoda's Wikipedia page, nor Mitsuya's. As far as I can tell, his only acting roles under his birth name seem to be in one episode of The Mysterious Detective Yutaro Hatori and the Fledgling Female Detective and a fairly decent recurring role in five episodes of Edogawa Ranpo's Beauty Series, which his uncle also appeared in. To my knowledge he and Hirata were never in anything together, but in addition to Beauty Series, both of them also guest-starred in separate episodes of Kumiko Oba's Comet-san in 1978.

Masayuki Onoda acted under different names (Masahiro Tsuji, Masayuki Mitsuya) much more extensively: for one, he frequently appeared in Kichiemon Nakamura's Onihei Hankacho series, which his father directed many installments of. I'll refer to him with the name Mitsuya as that seems to be what he goes by now. He is, or at least was at some point, married to actress Yuki Nohira.

Here he is in the opening credits of Edogawa Ranpo's Beauty Series. I believe he was just a few years younger than his uncle was when he played Dr. Serizawa here.

Not only was Mitsuya an actor: Later in his life he became the director of Mitsuya Production Co., which at one point ran Onihei Juku, a tutoring school that taught young actors an extensive course on jidaigeki (including swordfighting instruction, hair and makeup, dialogue, language, and history). Yoshiki Onoda also taught at the school. As of 2009, Mitsuya had a blog for the school where he posts occasional pictures of his father (which are actually extremely hard to come by). I will also draw your attention to the fact that his birthday is July 24th. I already thought it was pretty remarkable that the Onoda family had two birthdays and one death all within the month of July, but now I know that they actually have three birthdays in July.

After finding out about him, I rewatched episode 46 of Kagaku Sentai Dynaman, which he has a fairly prominent guest role in. Sayoko Hagiwara, who played Rei Tachibana/DynaPink, met up with him again in 2018, which is the most recent mention of him I'm aware of.

I might have cried watching Dynaman today, which is not something I thought I'd ever be saying.

I also want to mention that Yoshiki Onoda and Utako Mitsuya had one other, younger son, who I cannot find any information about. Presumably this other son was not in the acting industry as most of his family was, or else I would imagine I'd be able to find him some way or another.

I did not know Hirata had any living relatives. And they’re not even old. I've never heard that Yoshiko Otowa had any children (and her husband died at just 56 or 57 as well), so these two sons and whatever children they might have could be his only living relatives, if his siblings aren't still alive; nobody seems to know whether or not they are.