Triton of the Sea - Episode 20

NOTE: This summary is based on an imperfect translation (I do not speak Japanese). Please let me know of any inaccuracies.

Triton of the Sea is copyright 1972 by Office Academy. This summary is an effort by a fan for fans.

"The Jail of the Sea Spider"

Poseidon is told that Pipi and Fin are in the jail of Heptapoda, a
foolish Poseidn who longs for the sight of the sun. That was why
she is imprisoned in the jail of the sea spider. Poseidon remarks that
Heptapoda won't fight, but Neleus tells them that she might if
she is told she will see the sun. (Poseidon, of course, has no
intention of keeping this promise).

Karo talks to some fish, who saw a bright light and tell them
about a strange monster.

In the sea spider's web, Pipi and Fin see a woman in green followed
by swordfish and a Marcus. Marcus tells them that she can see the sun
when she kills Triton. She can use the sea spider to help her out.

Triton and the others come across the sea spider's webs, which only the
Oriharucon can cut. Luka worries about the dagger, but Triton is able
to cut his way through the webbing. He comes across Heptapoda,
who attacks him with transformed swordfish. She traps him in
a web and prepares a wall of swordfish to kill him.

Triton manages to destroy all the swordfish with the Oriharucon's
glow and escape, but the effort drains him and the dagger of energy.
Heptapoda finds Triton, who taunts her for being afraid of the
dagger's light when she loves the sun so much. She asks if the
light of the dagger is the same as the sun. Triton tells her that
the Poseidon can never live under the brilliant sun the Triton fight
for. Heptapoda calls him a liar. Triton waits for his dagger to
recharge as the sea spider creeps closer...

The sea spider reaches them and attacks. Heptapoda runs, hoping that
she can get out while the spider and Triton are distracted.

Heptapoda escapes and reaches the surface. When she emerges, the
sunlights shocks her, and she falls back into the water. She realized
that her dream of ten years can't be realized.

Triton fights the spider, trying to conserve the Oriharucon dagger's
energy as much as he can. He is finally able to stab the spider in
the head, and it falls back...from wounds made by the sword(fishes)
of Heptapoda! She tells him that she has given up her dream of the sun
and wants to kill the spider.

The spider webs her and tries to drag her in, but Triton stabs the spider again. Triton, Heptapoda, the dolphins, and a rescued Pipi and Fin escape the cave.

Poseidon tells his followers that neither Heptapoda or Triton will
survive.

Heptapoda disappears, and the others keep on toward the Atlantic.