"Summer's Crossing" picks up where "The Iron Queen" leaves off, with Puck and Ash watching as Meghan leaves her home (back in the mortal world), to return to the (well, her) Iron Realm.
Puck and Ash are in search of Grim, although they aren't entirely sure where to find him. While discussing where to start their search, Leanansidhe, Queen of the Exiles, comes to collect on a debt from the Winter Prince. She needs Ash, and Puck, to enter the Summer Court and retrieve a `violin' that was stolen from her by Queen Titania. In return for her `violin', Leanansidhe suggests she may be able to point them in the direction of Grim.
With a debt to repay, Ash, along with Puck, set out to retrieve Leanansidhe's `violin' from the Summer court. But when Puck runs into Oberon, who is out hunting, he proposes that if he somehow got rid of Ash, he'd have Oberon's approval to be with Meghan. Puck battles between helping Ash or letting Queen Titania, so that he can be with Meghan. Ultimately, in a way...Puck chooses both outcomes. Using glamour, he exposes the "Winter Prince", while the real Prince goes to rescue the `violin'.
I really enjoyed this novella, mainly because it was nice seeing things from Puck's perspective. Sure, he's a jokester, and we still see plenty of that in "Summer's Crossing", as well as throughout the series, but you get to see how he truly feels about Meghan, and how he wants her to be happy. Even if she is in love with his sworn enemy.
And I'll leave you with a quote from "Summer's Crossing":
"But he'd done it anyway, because of her. Because of the girl we were both crazy for, who was now far away, beyond our reach. Meghan."