The episode begins with the adventurers in the forest of the Elf King, where they encounter a large, elephant-like creature, Mokele Mbembe, ridden by a goblin. This unusual pairing causes confusion and concern within the group. They quickly conclude that the goblin does not have full control over the creature but is using it to wreak havoc.

The Goblin Slayer, always focused on his mission, decides that eliminating the goblin rider is the top priority. The group prepares for a strategic attack, with the Priestess ready to heal and the others taking up combat positions. They successfully bring down the Mokele Mbembe by capturing it without harming it, showcasing their skill and teamwork.

In the aftermath, the adventurers engage in conversations that reveal more about their backgrounds and motivations. Notably, the Elf Archer shares a poignant conversation with her elder sister about the fleeting nature of human life and the importance of friendships and farewells.

However, the threat of goblins looms large, and they remain vigilant. The adventurers discover a goblin nest upstream, posing a danger to the elf community and the river. They discuss how to approach and attack the nest, considering both land and water routes. Despite the risks, the group opts for the water route and prepares for the upcoming battle.

As they travel along the river, they encounter fog, further complicating their mission. They stay alert, knowing the goblins could attack at any moment.

The episode ends with the adventurers uncovering the goblins' plan to poison the river. They find evidence of the goblins' activities and resolve to stop them. The group also comes across a locked door, which they manage to open, hoping to learn more about the goblins' schemes.