Summary The book Son Of Neptune is about how a demigod named Percy Jackson loses his memory and is sent to camp Jupiter by Hera (the Greek aspect) or Juno (the roman aspect) the goddess. Percy wants to gain the romans trust. But, the roman doesn’t trust him because one his dad is Neptune/or Poseidon two because they don’t know anything about him except the fact than at he was sent by a goddess. So then at the end of capture the flag, Mars or Ares show up claims his son Frank and command Frank Percy and one other person to go on a quest. that other person was hazel levesque daughter of pluto or hades. They go to alaska and fight the giants. THEy find a lot of celestial bronze and imperial gold weapons and rode home on Arion the world 's fastest