Fun fact: there are only like two or three lines of Russ Tamblyn's on-set dialogue that exist to the public. They're in the Japanese trailer. And he sounds incredibly bored. He's dubbed by different actors in the Japanese and export versions (and ironically the English speaking performer sounds just about as bored as Tamblyn looks on film). Russ had the chance to fix the problem when he looped his dialogue for the U.S. release but he's just as bad there. Reportedly he didn't have his original dialogue at the looping sessions so he was forced to come up with close approximations. Maybe that had something to do with it, but I think he just didn't care: by his admission he took the role to see Japan.
And to be fair to Russ, he has spoken about how poor his performance is in recent decades. I don't think he ever saw the completed film until a film festival for Godzilla's 50th in San Francisco, where he was a guest of honor. As I recall he said after the screening that he enjoyed the movie but thought his performance was embarrassing. And let's face it, it is. He makes Rhodes Reason's performance in King Kong Escapes
LegendZilla wrote:That raises another question, was the film originally filmed with a dark filter?
No, the LD transfer used by Classic Media is just that bad
. The transfer of the US version on the same disc is probably pretty close to how the film should look. Toho's HD transfer on the Japanese Blu-Ray and now being used by Janus Films has more muted colors than the aforementioned transfer of the US version but no scene is as dark as any on the LD transfer.