This was the first sub in the book, and it carried the virus that would be acquired fifty years later for Kang to plot his destruction of the US. An American vessel sank the sub during wartime.
The protagonists thought they were successful at stopping Kang, because they found the viruses in I-403, but then the I-411 was discovered to still have some. Without this second payload, the plot would have been foiled early on.
A two person vessel is used by Dirk and Summer to retrieve the canisters from the I-411. They have a harrowing brush with death in it, but escape because of their ingenuity. When they surface with some of the canisters, they are greeted by Kang's henchmen, who instruct them to return to the I-411.....
