This is a classic Grass story told at different levels all inter connected and all being slowly peeled back like an onion. When they collide you hit the centre.
A washed up journalist born in a war time disaster is pushed by his mother and some sort of creative writing teacher into putting down his experiences on paper. They focus on his arrival into the world which coincided with the sinking of the Wilhelm Gustloff.
His mother was on board the ship and the sinking, as a result of a Russian submarine torpedo, ended a vessel that had started life as a Strength Through Joy holiday ship.
The ship is sunk when it is carrying refugees, injured soldiers and the ships crew. That is one strand of the story telling the story of that night.
But there is also the historical context with the ship being named after the leading Nazi agitator in Switzerland who becomes a martyr after being shot at close range by a Jew determined to settle some scores for the abuse of his people in Germany. That story along with the added history of the Russian submarine captain is the second strand.
Then the third strand is the conflict between father and son after the narrator discovers that under the influence of his mother his son is spouting off pro-Nazi views about the ship.
The battle is being fought in cyberspace and there is a comment there from Grass about the contest online for the hearts and souls.
The book flits back and forth between the strands but they are all being peeled back and the sense of a showdown between the ships hull and the torpedo, father and son and truth and lies is always hovering over the narrative.