This episode was also known as "Lupin Gets Interred" or "Lupin the Interred"
This episode ranked #15 in the Lupin III Best Selection rerun of favorite episodes, as chosen by Japanese fans.
Lupin's eyes are open when Jigen and Goemon pull him out of the water, but in the flashback, when he floats to the surface, they're closed. This is probably because he's numb and delirious from the sleeping pills he took as part of his plan and is unable to speak or do anything else.
Richard Epcar, the English dub's director and the voice of Jigen, reads aloud the inscription on Lupin's tombstone.
The English dub characterizes Zenigata as an unadulterated tsundere when he's grieving over Lupin's apparent death. He outright tells Lupin he loves him, then gets angry at him for dying, then apologizes.