Jack leaps into the water to rescue his son from the unseen menace and they swim to the safety of the shore where Gideon has found a bottle. Back at Granite House a message is pulled from the bottle‹written by a fellow castaway on the island! Jack, Herbert and Gideon set out on a test voyage in their boat to locate the castaway. They find his well-stocked camp and gather up supplies as no one is in sight. Mr Ayrton soon makes an appearance and Herbert convinces his father to take him back with them. Meanwhile, Joanne, while out by herself gathering plants, is overcome by Nemo's gas devise and falls unconscous. When Neb goes to search for her, he too is overcome but before he collapses, he sees Nemo approach. Back in Nemo's lair, Nemo posions Neb, making it appear to be from a snake bit. Harding later finds Neb's body and a memorial service is held, with Harding biding a tearful farewell to his dear friend.

杰克跳入水中，把儿子从看不见的威胁中救了出来，他们游到了吉迪恩发现一个瓶子的安全岸边。回到Granite House，有人从瓶子里拿出一条信息，是岛上一个漂流者写的！杰克、赫伯特和吉迪恩乘坐他们的船开始了一次试航，以寻找遇难者。他们找到了他储备充足的营地，在看不到任何人的情况下收集了补给。艾尔顿先生很快出现了，赫伯特说服他的父亲带他回去。与此同时，乔安妮虽然独自外出采集植物，却被尼莫的天然气设计所征服，并没有受到影响。当纳布去寻找她时，他也被征服了，但在他崩溃之前，他看到尼莫靠近了。回到尼莫的巢穴，尼莫·波西恩斯·内布（Nemo posions Neb），看起来像是被蛇咬了一口。哈丁后来找到了内布的尸体，并举行了追悼会，哈丁含泪告别了他亲爱的朋友。