Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Exposition
There's No Crying at Experiment House
The adventure of The Silver Chair really begins because Eustace and Jill call out to Aslan to take them away from their hideous school, where the idea of safety and justice is nothing more than a distant concept. Aslan will later say that he was calling to the children first, which means that his timing was impeccable. The bulk of the exposition ends after Jill receives her instructions and the children attend the parliament of owls, during which they learn of the circumstances of Rilian's disappearance.
Rising Action
This Ain't No Pleasure Cruise
Jill and Eustace spend a large portion of their journey making mistakes and bad decisions. Go team, right? As they move toward the central conflict of the work (facing the Queen of Underland), they have a hard time recognizing the signs (they miss three out of four), coping with the cold and hard living on Ettinsmoor, catching their own food, and encountering creatures that, to be frank, frighten the bejeebers out of them.
Jill and Eustace also have to contend with their short tempers and other shortcomings, which the hardships of travel unfortunately exacerbate in the extreme. It's no pleasure trip, for sure. Despite what appears to be a critical lack of success in getting on with the quest, the children and Puddleglum wind up exactly where they're supposed to be: under the ruins of the giants' ancient city.
Climax
Free at Last?
The most gut-wrenching part of the quest is the moment when the three adventurers have to decide whether to free the raving Black Knight from the silver chair. Lewis describes it as a "dreadful question" (11.166) and tells us that the seconds before Puddleglum and Eustace free him are actually "sickening" (11.167). The difficulty? They have to choose between competing duties. They've just promised each other not to release the Black Knight, but on the other hand, they've been commissioned by Aslan to follow the signs. It's a major conundrum.
When the queen catches them right after, though, and attempts to enchant them all with her magic, we find ourselves with another critical moment in which the children and Rilian lose their conviction in Aslan's existence. It's a tense moment, because the loss of that memory would cause a total collapse of, well, everything. But Puddleglum clears the air (quite literally) by stamping on the enchanted fire with his frog foot, lifting the fog and paving the way for the destruction of the queen and her dark magic.
Falling Action
Stepping Out
Once the adventurers—now including Prince Rilian—realize that the Earthmen will not stop them from escaping Underland, it's just a matter of getting out. Rilian has a momentary lapse of reason that could sidetrack them with a trip to Bism, but Puddleglum once again saves the day. The moment that Jill pokes her head through the hillside in Narnia and the Narnians recognize Rilian as their prince, the quest is effectively at an end.
Resolution
The Healing of Harms, or How to Fix Everything in One Chapter
The children and Puddleglum have been through quite a lot by the end of the journey, to say nothing of what Rilian and Caspian have suffered over the years. But by the time Rilian reaches the quayside at Cair Paravel, all of this discomfort matters no more—the focus is entirely on the blessing of Rilian, about three seconds before the old king passes away. In this act of blessing, Caspian receives his lost son again and presents to his people their new sovereign. Problem solved.
But Aslan wants to take it one step further and make things right for Caspian, who has been a good and loyal subject. The resurrection of Caspian on the mountain also serves another function: It heals the hearts of the children, who are weary from their journey, the loss of a friend, and the feeling that they didn't do as well as they should have. Lewis brings all to rights when the bullies at Experiment House get their comeuppance and real, positive changes are promised in the daily lives of Jill and Eustace.