Following Sultan Murad's unexpected death, the Ottoman palace mourns and a new era begins. The question arises: will Mehmed or Orhan ascend to the throne? Despite İshak's opposition, Çandarlı supports Mehmed's succession, fearing unfortunate consequences. Mehmed, cautious of potential plots, sets out carefully with his servants. Constantine plans to hinder Mehmed, favoring Orhan's ascension. Orhan, closer to Edirne and with a better chance at the throne, rejects Konstantinos' offer for help, knowing it would not be welcomed. He faces an unexpected obstacle, Bali Bey, whose intentions remain unclear.

Sultan Mehmed crushed a Janissary rebellion, executing Ali Haydar and his followers. He then sent Battal and Bali Bey to eliminate bandits, capturing Ferhat’s chamberlain, Beşir, and questioning Ferhat Pasha's loyalty. The Ottoman army attacked Constantinople with the Şahi cannon, creating a breach at the St. Romanos Gate. Despite heavy resistance and losses from Byzantine defenders, the Ottomans continued their advance. The battle's outcome would decide if Constantinople would become Istanbul.

During the Ottoman attack on Constantinople, Sultan Mehmed is wounded by a Byzantine soldier, leading to a temporary retreat. Sultan Mehmed, initially despondent, is inspired by Akşemseddin to renew his belief in conquest. He sends Ferhat Pasha as an ambassador for a prisoner exchange, but Ferhat is suspected of being a spy. Ferhat is captured and brought before the Sultan. The unfolding events will determine the fate of the Ottoman army, the revelation of traitors, and the ultimate success of the conquest.

Sultan Mehmed faces a turbulent chapter marked by personal grief and political upheaval, as the critical condition of Prince Beyazıd stirs unrest within the palace. Amid rising tensions in the imperial court—fueled by rivalries between Mahmud Pasha and İshak Pasha, and debates over Zağanos Pasha—Mehmed navigates shifting alliances against Karaman, Pontus, and the Vatican. While Beyazıd clings to life, Mustafa is ceremoniously inducted into the Janissary corps and sent on campaign. As Vlad Tepes plots in Pontus and the Karatuğs endure torture, Basat grows wary of betrayal. Mehmed’s decision to recall Zağanos Pasha signals a pivotal shift, just as the Ottoman army marches toward Beyşehir, where an impending battle and palace power shifts will shape the empire’s destiny.

After Prince Ahmed's death and Kurtçu Doğan's execution of Mehmed, Mehmed declares a new era, removing Kurtçu Doğan from Ocak Ağa and punishing the rebels. He reaffirms his goal of conquering Constantinople. Constantine, having exiled Notaras and brought in Sfrancis, tests Mehmed's stance on peace by sending an ambassador again. Meanwhile, Helena plans to marry off Constantine, seeking a suitable wife. In the harem, Halime's time ends as she passes away following Ahmed's death. Gülşah intercepts a letter sent to Mihriban, adding intrigue regarding Hala Sultan's involvement.

The Ottoman army, led by Zaganos, faced resistance at Dimitria Castle. When hope seemed lost, Sultan Mehmed arrived, inspired his soldiers, and ordered a final attack, aiming for victory. Meanwhile, the Hurufis, taking over provisions and spreading propaganda in the capital, face a new challenge as Mehmed is determined to protect his state from corrupt beliefs. Mara, seeking to undermine Byzantium through Hala Sultan, gains Mehmed's permission for her plan. Konstantinos, upon learning from his mother Helena why the castle was lost, plans to issue a harsh punishment to set an example.

After conquering Dimitria Castle and defeating the Hurufi plague, Mehmed sets his sights on Constantinople. He tasks Evrenosoğlu with eliminating Orhan, aiming to trap him with a plan involving Hala Sultan. Meanwhile, Konstantinos, seeking to recover from his defeat, sends Sfrancis to attack the dervishes, hoping to prove the Turks cannot establish themselves. This draws the Ottomans towards him, and Çandarlı marches to confront Sfrancis. In the harem, Halime plans to kidnap Hala Sultan, who is awaiting her fate. The outcome of this plot remains uncertain.

While campaigning against Karaman, Mehmed invites Evrenesoğlu Ali to handle potential issues in the capital, appointing him as the palace trustee. Çandarlı, remaining in the capital, plots to place Ahmed on the throne by manipulating Gülşah, facing obstacles from Halime who also aims to make Ahmed sultan. Konstantinos makes a risky offer to increase Orhan's allocation to quell discontent about Orhan's expenses, awaiting Mehmed's response. Kurtçu, following Çandarlı's orders, plans to intercept Mehmed and challenge him to pass under swords, risking conflict with the Janissaries. The unfolding events create a tense atmosphere, with Mehmed's decisions and responses critically shaping the outcomes.

Constantine reveals the truth to Mehmed when handing over Mara, exposing Çandarlı Halil's collaboration. Mara must decide whether to inform Mehmed or confront Çandarlı herself. Tired of political games, Mehmed sets his sights on conquering Dimitria Castle. Mara's return causes concern for Hala Sultan, prompting her to warn Mihriban. Mara devises a dangerous plan to expose Hala Sultan. The outcome of this scheme remains uncertain. Constantine seeks to bolster his city's security and considers seeking help from the Vatican, despite opposition from Helena and Sfrancis. The success of this unity and Constantine's plans hinge on overcoming these internal disagreements.

Mehmed embarks on his conquest with a desire for martyrdom. His success depends on his staff agreeing on the strategy and shaping his policies towards his vizier and the Janissaries. Hamza's wounding affects the Malkoçoğlu tribe and the Rumelia Beylerbeylik, with moves expected from Çandarlı and Zağanos Pasha. Guistiniani suspects Mehmed's spy Mustafa and needs to present proof to Emperor Constantine. Nadia seeks validation from Guistiniani despite her romantic entanglement with Anna. Notaras, implicated in Cardinal Isodor's murder, seeks assistance. Demetrios, grieving his child's death, must decide on his political allegiance. The safe arrival of Mehmed's Şahi cannon is crucial, while the Grejuva master must meet Konstantinos' expectations. Internal conflicts among the Janissaries add tension. These events will determine the outcome of Mehmed's conquest.

After the assault on the Walls, Mehmed's decision will impact the course of the conquest. Kalender's mention of a brave raider to Mehmed hints at a potential game-changer for the conquest. Orhan's aide in Constantinople and Mustafa are revealed as spies, affecting Mehmed's side and prompting Ferhat to take action. Meanwhile, Janosh, motivated by revenge from the Kosovo War, may disrupt Mehmed's plans. Çandarlı Pasha's schemes for Kalender Ağa and Ferhat Pasha aim to strengthen his influence over the Sultan. The new danger awaiting Bali and Hamza tests their resolve. Constantine, under siege and pressure, makes moves to defend his city. Giustiniani's emotional connection with Anna could impact his motivation and effectiveness in defending Constantinople against the Turks.

Sultan Mehmed assigns Admiral Suleyman Pasha to stop the Pope's aid to Constantinople. Mehmed watches the naval battle from the shore. Satılmış Ağa helps overcome a large rock, allowing Mehmed's attack plan to proceed. Mehmed orders his staff into action, with Battal Bey, Saltuk, and Satılmış Ağa taking on a dangerous mission. In Byzantium, Constantine is betrayed and wounded by Anna, who is imprisoned. Nadia plans revenge against Byzantium and Guistiniani. The tension between Kurtçu Doğan and Kalender rises, with Kalender seeking the position of Janissary Agha and Kurtçu angering Mehmed. The outcomes of Suleyman Pasha's mission, Mehmed's attack, and the internal conflicts in Byzantium will shape the fate of Constantinople.

On the night of his wedding, Mehmed embarks on a risky journey to Constantinople to save Zağanos, collaborating with an unexpected ally from the Byzantine palace. He also meets Urban, hoping to convince him to return. Mehmed's plans are shattered by news of his mother's death, causing him to question his father. His departure to Constantinople causes chaos in Edirne Palace, prompting İbrahim to confront Murad about Gülşah. Meanwhile, Helena and Notaras, aware of Turkish infiltrators, plan to capture Mehmed, which causes tension between Konstantinos and his mother Helena. The success of their plans and Mehmed's fate hang in the balance.

Prince Mehmed, ambushed by the poor, fights fiercely as İshak approaches with his men. Mehmed later returns to Edirne and moves his harem to Manisa, where he receives a letter to Gülşah prompting a journey to Karamanoğlu. Murad deteriorates after Hüma's death, causing concern for Çandarlı, who contemplates measures for the state's future. Mehmed, aware of the situation, leaves Şehabeddin in Edirne. In Byzantium, tensions between Konstantinos and Helena intensify as Konstantinos prepares to make significant changes, with Helena and Notaras posing major obstacles.

After ascending to the throne, Mehmed confronts Halime for attempting to kidnap Ahmed and Çandarlı for his alleged complicity. Halime faces a choice: implicate Çandarlı or remain silent. Mehmed establishes a new order in the palace and must decide on the Grand Vizier. In the harem, Bahar becomes the chief haseki, marking a new era. Hala Sultan's unexpected arrival disrupts the harem's order, and her first move targets Halime. Gülşah is placed under Bahar's influence by Mehmed. Çandarlı plans a new strategy against Mehmed, using Piri Pasha's arrival to pit the Ottomans against Karaman. The unfolding events set the stage for further political intrigue and power struggles.

After thwarting Byzantium's plans and responding to Notaras, Mehmed continued his conquest preparations, warning his pashas to stay vigilant, especially Baltaoğlu. However, Baltaoğlu fell victim to Konstantinos' plot. Çandarlı, seeking revenge for his nephew Hayreddin, focused on finding Rizzo. Konstantinos, seeing the failure of alliances with the Serbs and Karamanoğlu, sought the Pope's support but was rejected, except by Giovanni Giustianni, who nonetheless set off for Constantinople.

Mehmed holds Baltaoğlu Süleyman Pasha accountable for Guistinianni's entry into the city, facing a potential execution. Çandarlı may try to persuade Mehmed to change his mind. In the harem, Prince Beyazıd's discomfort might continue due to the attention given to Mustafa. Meanwhile, the Balinese pursuing Demetrios in Mora face various challenges and obstacles, with Demetrios and his wife Theodore plotting their own strategies. In Constantinople, the arrival of Guistinianni's soldiers will impact the city's atmosphere. Both Ottoman and Byzantine sides prepare for tactical battles before the siege, with Mehmed planning his moves towards the city's walls and gates. The responses of Zağanos, İshak Pasha, and other Kubbealtı ministers to Mehmed's strategies, as well as the defensive plans of Konstantinos, Notaras, and Giustinianni, will shape the upcoming conflict.

Mehmed questions Gülşah and Bahar, blamed for Prince Beyazıd's condition, about their responsibilities. The harem's roles might change, with Mara Hatun managing potential conflicts. Demetrios, grieving his child's loss, considers avoiding the Byzantine-Ottoman conflict, while Theodore, devastated, urges him to leave for Morea. In the Ottoman court, Zağanos Pasha, who acted without Mehmed's approval, faces potential consequences once Mehmed learns the truth. Guistiniani, arriving in Constantinople, aims to defend the Golden Horn against the Turks, while the Emperor strategizes amidst internal disagreements. Guistiniani also targets Turkish spies in the city. In Galata, tensions rise as Notaras deals with Lomellino, who sides with the Turks, and Janissaries are sent to protect the Golden Horn chain. Sultan Mehmed calls for an unprecedented consultation with the sanjak beys, including Teke Sanjak Beyi Ismail, whose political stance before the siege remains crucial.

Urban and Mehmed insist the damaged Şahi cannon be detonated, tasking Saruca with this risky mission. The explosion's aftermath for Mehmed is uncertain. Çandarlı aims to win Mehmed's favor for Kalender and isolate Kurtçu politically. Çandarlı, Zağanos, and İshak Pasha hope to use Plethon's peace call to their advantage, questioning if they realize it's a ploy. Demetrios, grieving his child, seeks Hamza. Alperen, having volunteered without consulting his father, contemplates his actions post-discussion. Konstantinos searches for Cardinal İzodore's killer, awaiting crucial news. With the Turks nearing, Konstantinos plots his next move. Orhan and Mustafa face potential danger. Emotional ties between Guistiniani and Anna develop, while Guistiniani's suspicion of Notaras in Isodore's death is under scrutiny.

Mehmed, recovering from a defeat, prevents an epidemic in Rumeli Hisarı with Kurtçu's help, earning Kurtçu the Sultan's pardon and foiling Kalender and Ali Haydar's plans. Kalender seeks Çandarlı's support to replace Kurtçu, leading to a radical new plan. Ferhat Pasha orders a raid on the Sultan's caravan carrying a cure for the epidemic. Battal and Bali Bey are dispatched to stop Dugin and his men. Ishak Pasha grows suspicious of Ferhat Pasha, who tries to deflect suspicion by claiming to save Mustafa. On the Byzantine front, Guistiniani's soldiers join Salvador's troops. Demetrios announces his intent to marry Anna to the senate, potentially altering the balance in Byzantium, and awaiting Konstaninos' reaction.

Mehmed narrowly escapes an ambush by Janosh and faces the challenge of assisting his father, Murad, who is under attack from Wallachians with explosive pots. Murad must also defend himself against a sneaky Wallachian. Upon returning from the victorious Kosovo War, Çandarlı seeks revenge on Mehmed by setting up a scheme during Zafer Toyunda. Mehmed and Gülşah's marriage occurs with Sultan Murad's and İbrahim Han's permission, despite Mehmed's reluctance, causing concern for Bahar. In the harem, Halime Sultan manipulates Murad to send Hüma to Bursa, worsening Hüma's illness. Halime continues plotting, now focusing on Gülşah as Mehmed's wife.

A cannon explodes near Mehmed, turning the area into chaos. Quickly removed, Mehmed faces more disappointments, including a fortress raid and Mara's kidnapping, pushing him to demand accountability from the betrayer and the careless. Konstantinos, having kidnapped Mara, tries to convince her to marry him, but Mara stands firm. The outcome of this struggle remains uncertain. Orhan seeks revenge on Bali, whose fate is in question. Hala Sultan, having created space by removing Mara from the harem, has new goals. It is uncertain whether Bahar and Gülşah will counter her moves or if Hala Sultan will dominate the harem.

Mehmed, having overcome many obstacles, prepares for the siege of Constantinople, uniting his viziers and subjects. He strengthens the navy, led by Baltaoğlu, who aims to reunite with his brother, Rizzo. Çandarlı makes Rizzo grateful to the Ottomans, and Mehmed sets his plan on Rizzo, whose help is crucial. In the Harem, preparations for the siege continue, with Mara, Bahar, and Gülşah actively involved. Gülşah's pregnancy adds excitement, with the upcoming birth expected to change the harem's dynamics. In Byzantium, the fear of the Ottomans grows, and Constantine, struggling to make decisions, is advised by Plethon to call Notaras back. This decision's impact on the Byzantines remains to be seen.

After weeks of relentless effort, the Ottoman army breaches Constantinople’s formidable walls, bringing Sultan Mehmed to the brink of his long-awaited victory. However, an unforeseen obstacle threatens to unravel his plans. As Ottoman forces push deeper into the city, they unknowingly walk into deadly traps set by Emperor Constantine, facing street-by-street resistance. With treacherous secrets lurking behind the supposedly impenetrable walls, Mehmed and his fearless army must overcome these final challenges to secure their historic conquest and usher in a new era.

Following the conquest of Constantinople, Sultan Mehmed worked to rebuild the city as a Muslim-Turkish homeland, uncovering and thwarting a major assassination plot while executing Prince Orhan, a longstanding threat to the Ottoman Empire. Determined to leave an Ottoman legacy, he initiated sweeping reforms, reshaped the administration, and commenced the construction of the Fatih Mosque, though an incident at the site deeply impacted him. Amidst these changes, a secret organization led by Plethon and Notaras began plotting, exploiting weaknesses to advance their ruthless goals, creating new challenges for Sultan Mehmed as he pursued his vision for the empire's future.