3.5 - 4 stars
"Percy Jackson? He's too loyal to his friends. He can't give them up, not for anything. He was told that, years ago. And someday soon, he's going to face a sacrifice he can't make. Without you, Frank - without your sense of duty - he's going to fail. The whole war will go sideways and Gaea will destroy our world."
Which is as may be, but I also think his loyalty is the one thing that will unite the seven and keep them together.
Why does Percy think he'd seen Sammy in the 1941 photo?
Thanotos tells them they will need a guide to the doors of death - "Only one sort of demigod can read the signs that will ultimately lead you to the Doors of Me."
Which is Nico or Hazel, obviously. Regardless, I really, really want Nico involved in this quest and I would like to see him doing more with Percy and Jason. He has so much potential as a character...
Then there is Juno warning Percy that Annabeth will cause the most trouble for the quest. Hmm? Why? And what hard task lies ahead for her in Rome?
So, good movement forward of overall plot, get to meet Frank and Hazel, as well as seeing what Percy was up to these past few months. And a few enigmatic prophecies, foreshadowings and completely awesome Percy scenes!
The Mark of Athenahas a lot of good stuff coming!