Clockwork Princess by Cassandra Clare

Book Summary

Clockwork Princess by Cassandra Clare

Clockwork Princess is the third book in Cassandra Clare’s Infernal Devices trilogy.


Tessa is amidst the excitement of trying on her wedding gown when a sudden disruption occurs at the London Institute.

Gabriel Lightwood bursts in with startling news: his father, Benedict Lightwood, has undergone a bizarre transformation into a worm-like creature.

Will Herondale grimly reveals the cause behind Benedict’s grotesque change—a dreadful affliction known as demon pox.

Determined to aid their friend’s family in this dire situation, Tessa embarks on a journey with Gideon and Gabriel Lightwood, along with Will, Jem, Cicely, and her betrothed, to the Lightwood estate.


Upon arrival, chaos unfolds as Will and the others engage in a fierce battle against the worm-like demon, while Tessa takes charge of the Lightwoods’ sister, providing comfort and assistance amidst the turmoil.

In the midst of the chaos, Tessa’s calm demeanor and quick thinking prove invaluable as she helps to maintain order and support her companions.


As the dust settles and the danger subsides, Tessa finds herself drawn into a deeper mystery alongside Henry.

Together, they uncover cryptic writings adorning the walls of Benedict’s study, hinting at the existence of the elusive Infernal Devices—mechanical creations with ties to the nefarious plans of Mortmain.


After the intense battle, Gabriel’s heart-wrenching act of killing his own father leaves everyone reeling.

But the shock doesn’t end there. Jem, already weakened by his illness, collapses, sending waves of alarm through their group.

It’s a devastating revelation: Jem has been secretly using yin fen, a dangerous drug he’s addicted to, and now he’s dangerously low on it.


In a frantic frenzy, Will, driven by an overwhelming sense of desperation, dashes through the streets of London in a desperate attempt to secure more of the life-saving substance known as yin fen.

However, his frantic efforts are met with a bone-chilling realization—a mysterious force has swept through the city, snatching up every last vial of yin fen, leaving Will and his companions in a state of utter panic as they come to grips with the dire consequences of this scarcity.


As the gravity of the situation sinks in, a sense of dread envelops them, knowing that Jem’s very existence hangs precariously in the balance.

With time slipping away and their options dwindling, Jem implores Will to leave no stone unturned in their search for a solution, for a glimmer of hope to prolong his dwindling life.


With heavy hearts and minds clouded by uncertainty, Will and Tessa find themselves turning to the enigmatic figure of Magnus Bane, a renowned wizard rumored to hold secrets beyond the grasp of mortal understanding, and who has also helped Will before.

Clinging desperately to the faintest shred of hope, they beseech Magnus for aid, praying that he may possess the knowledge, the power, or perhaps even the elusive cure that could save Jem from the clutches of impending doom, or at the very least, provide a temporary reprieve from the grim fate that looms ever closer.


As Jem’s condition deteriorates, a dark cloud of fear looms over Tessa, threatening to shatter their dreams of a life together.

With each passing day, the specter of death draws nearer, casting a shadow over their hopes for a future filled with love and happiness. 


In a cruel twist of fate, Mortmain, their relentless foe, exploits their vulnerability, offering a sinister bargain: more yin fen in exchange for Tessa.

Desperate to save Jem, Tessa reluctantly agrees, only to be met with fierce resistance from her beloved, who even went as far as to throw the tiny bit of yin fen that with the letter into the fire.

Despite Jem’s unwavering determination to protect her at all costs, the decision is cruelly ripped from Tessa’s grasp when a horde of automatons descends upon the institute, snatching her away against her will.


As Tessa is torn from the safety of her home, the harrowing reality of their situation sinks in.

With Mortmain’s grip tightening around them, Tessa and her companions are thrust into a perilous struggle for survival, their every move fraught with danger and uncertainty.


As Jem’s weakened form crumples to the ground in the aftermath of Tessa’s abduction, a palpable sense of despair settles over the London Institute.

Will, torn between the urgency of rescuing Tessa and the desperate need to remain by Jem’s side, finds himself immobilized by conflicting emotions. 


But amidst the chaos and turmoil, a poignant moment of clarity emerges.

Overhearing Will’s conversation with Magnus about his feelings for Tessa, Jem’s heart swells with bittersweet understanding.

In a selfless act of love and sacrifice, Jem embraces his own pain to ensure that the one he cherishes most finds solace and protection in the arms of another.


With unwavering resolve, Jem imparts his final decree to Will, his voice trembling with emotion as he bestows upon him the role of Tessa’s protector.

With a heavy yet determined heart, Will sets out on a perilous quest to reclaim the woman he loves from the clutches of Mortmain, fueled by the unwavering conviction that he will stop at nothing to ensure her safety and happiness.


As Will embarks on his journey to Wales, his heart weighed down by the burden of grief and uncertainty, he senses a profound shift—the moment when the unbreakable bond between him and Jem, known as the parabatai tie, is severed.

With a heavy heart, Will presses on, driven by a desperate need to find Tessa and confront the sinister forces that have torn their lives apart.


Upon reaching Mortmain’s stronghold, Will is met with a chilling revelation: the devastating news of Jem’s supposed demise.

Struggling to come to terms with the loss of his dear friend, Will finds solace and fleeting comfort in Tessa’s embrace, their love for each other igniting a spark of hope amidst the darkness that surrounds them.


However, their tender moment is short-lived as they awaken the next morning to an unexpected visitor—Magnus, the enigmatic wizard, who arrives bearing news of a breakthrough.

With Magnus and Henry’s ingenuity, a portal has been crafted, offering a glimmer of opportunity for the Shadowhunters from London to swiftly teleport into Mortmain’s lair.


Yet, their newfound hope is swiftly eclipsed by a calamitous turn of events.

In a moment of misfortune, Henry inadvertently triggers the awakening of the dormant automatons, plunging them into a frenzied battle for survival.

As chaos erupts and danger looms on every front, Henry finds himself grievously wounded, his sacrifice serving as a stark reminder of the perils they face in their quest to vanquish the darkness threatening their world.


During the chaos of the battle, they learn that Jem is still alive and that he turned into a silent brother to live but just as Tessa starts towards him a sinister automaton seizes her, dragging her away from her companions.

As the dust settles and Mortmain commands the automatons to cease their onslaught, his chilling voice pierces the air, summoning Tessa to his side.

Faced with the grim reality of Mortmain’s nefarious intentions—to slaughter her friends and coerce her into a forced marriage—Tessa knows she must act swiftly to thwart his vile plans.


Drawing upon her innate ability to shape-shift, Tessa uses the angel soul that had been stuck in her necklace to transform into an angelic form, unleashing a divine fury upon Mortmain and vanquishing the source of their torment.

Yet, the victory comes at a great cost—Tessa’s own well-being is compromised, leaving her gravely ill and weakened by the strain of her supernatural exertion.


Upon their return to the safety of the institute, Will remains steadfast by Tessa’s side, his heart heavy with concern for her fragile state.

As he watches over her, a profound realization dawns upon Will: the bond between Tessa and Jem, once unbreakable, now poses a grave threat to their collective well-being.

Driven by a desperate resolve to safeguard their futures, Will implores Charlotte to summon Jem, who, in his transformation into a Silent Brother, embodies the physical manifestation of their shattered bond.


As Jem arrives, bearing his heart’s most vulnerable confession, he professes his love for Tessa.

Yet, amidst the tender words, a shadow of realization hangs heavy in the air—he acknowledges that Will’s affections for Tessa run just as deep.

In a poignant exchange, they grapple with the complexities of their intertwined destinies, recognizing the painful truth that their love triangle cannot endure unchanged.


Together, they arrive at a bittersweet resolution: it is time for Tessa to forge a new path with Will by her side.

With heavy hearts but a shared understanding, they pledge to honor their love by meeting annually at the London bridge, where their fateful encounter first ignited the flames of passion.


As Jem retreats to the enclave of the Silent Brothers, Tessa and Will embrace the promise of a future together, navigating life’s twists and turns as steadfast companions.

Their union blossoms into decades of mariage, marked by the joys of parenthood and the unwavering bond they share.


But as time marches on, Will’s mortal form succumbs to the ravages of age, leaving Tessa to wander the world alone, her eternal youth a stark contrast to the passage of time.

Yet, amid the solitude, her steadfast devotion to Jem remains unwavering, a beacon of hope that transcends the boundaries of mortality.


Then, in a twist of fate, Tessa’s world is rocked by unexpected news—Jem has found a cure for his affliction and cast aside the mantle of the Silent Brothers.

Faced with the prospect of a renewed future with her beloved, Tessa grapples with conflicting emotions, torn between the fear of loss and the enduring flame of love that has burned within her for over a century.

In the end, she realizes that true love knows no bounds, and she seizes the opportunity to embrace a second chance at happiness with the one who has held her heart captive for a lifetime



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Clockwork Prince is the second book in Cassandra Clare’s “The Infernal Devices” trilogy.   The book starts with Tessa Gray still living in the London