What Will You Do, Ieyasu？

The Warring States Period, when samurai vied for territory. Matsudaira Motoyasu, later known as Tokugawa Ieyasu, enjoys his life as a hostage with Imagawa Yoshimoto and falls in love with Lady Sena. But now Oda Nobunaga threatens this peace. Motoyasu carries out a risky mission but receives shocking news in the middle of battle! What will Motoyasu do!?

Yoshimoto has been killed in battle. Surrounded by Nobunaga’s forces, Motoyasu is in trouble. But Nobunaga suddenly retreats. Motoyasu tries to return to Sunpu, but his vassals opposed it, demanding to return to Mikawa. Reluctantly, he heads to Mikawa, but falls into a trap. A senior vassal is wounded, and his forces are almost destroyed. They flee to Daiju-ji temple in Okazaki, but...

On his return to Okazaki, Motoyasu vows to overthrow Nobunaga, but his small army stands no chance. Ujizane sends no reinforcements. Honda Tadakatsu suggests switching sides, but with Sena left in Sunpu, Motoyasu hesitates to betray the Imagawa. Then his uncle Mizuno Nobumoto arrives with someone unexpected: his mother, O-Dai, whom he hasn't seen in 16 years.

Motoyasu heads to Kiyosu Castle, where Nobunaga awaits. Once a hostage of the Oda, he’s now ordered to wrestle Nobunaga as a greeting. He meets Kinoshita Tokichiro and Nobunaga’s sister Ichi. In return for an alliance, Nobunaga demands a shocking condition. Meanwhile, in Sunpu, Motoyasu’s wife Sena is pressured by Ujizane to leave him and become his concubine.

Before taking on the Imagawa, Motoyasu resolves to rescue Sena, held in Sunpu. Against his vassals’ objections, he relies on the cunning yet distrusted Honda Masanobu, who devises a plan using the Hattori ninja clan. But the leader, Hattori Hanzo, has lost confidence due to past failure. Can Masanobu and Hanzo infiltrate Sunpu and bring Sena?

Masanobu’s rescue plan fails. Ujizane warns Motoyasu that if he doesn’t surrender, Sena and their children will be killed. Masanobu proposes a secret plan to capture a top Imagawa retainer and exchange him for Sena. Motoyasu stakes everything on this bold move. Hanzo infiltrates the impregnable Kaminogo Castle—and soon, flames rise. Is it a sign of success, or...?

Reunited with his family, Motoyasu changes his name to Ieyasu, hoping to unite Mikawa like a single household (“ie”). But unifying the land is far off. Sena tells him the Ikko Sect is gaining popularity. Ieyasu sneaks into Honsho-ji and hears the priest Kuzei blame the samurai for the people’s suffering. He orders action against the Ikko, triggering unrest across Mikawa.

Ieyasu tries taxing Honsho-ji, which causes the Ikko Sect to rebel. His attempts to quell them fail: their skilled strategist sees through all his tactics. Matsudaira Shokyu and other lords defect, even his vassal Natsume Hirotsugu betrays him. Ieyasu orders Hanzo to infiltrate the temple and incite unrest. There Hanzo discovers the strategist’s shocking identity.

The Ikko tactician was Honda Masanobu! Unable to trust even his closest retainers, Ieyasu shuts himself away. But Torii Tadakichi visits and tells him to either have faith even if betrayed, or sever ties if in doubt. Ieyasu makes his decision. After a fierce battle, he confronts Masanobu, who pleads with him to listen to the people. Tearfully, Ieyasu faces a painful decision.

Sena opens a hermitage at Tsukiyama, near Okazaki Castle, to hear the voices of the people. O-Dai, worried that Ieyasu only has two children, urges him to take a concubine. She selects O-Ha, a curt but attentive. Ieyasu spends the night with her, but she takes an unexpected action! Meanwhile, a coup erupts in Kyoto. Nobunaga and Shingen grow restless, and Ieyasu is swept into the tides of change.

Now lord of Mikawa, Ieyasu changes his surname to Tokugawa. He negotiates with Takeda Shingen and forms a secret pact: both will invade and divide the Imagawa lands. Though reluctant to confront the Imagawa, Ieyasu leads his forces towards Hikuma Castle in Totomi. However, the castle’s mistress is Sena's close friend, O-Tazu. Worried about her friend’s safety, Sena sends her a letter.

Ujizane, besieged by Shingen and abandoned by his retainers, flees Suruga. His wife urges him to go to her family, the Hojo, but he refuses. Instead, he escapes to Kakegawa Castle, near Tokugawa lands—forcing Ieyasu to battle the man who was once like a brother to him. As neither Ieyasu nor Ujizane is able to gain the advantage, they both reflect on their memories of Yoshimoto.

While Totomi, now Tokugawa land, remains unstable, Ieyasu travels to Kyoto by order of the new shogun, Ashikaga Yoshiaki, backed by Nobunaga. There, he meets Akechi Mitsuhide, merchant Chaya Shirojiro, and Azai Nagamasa, husband of Ichi. Upon meeting Yoshiaki, Ieyasu is baffled by his foolish behavior. Why did Nobunaga support such a man? What is his true intention?

Ieyasu joins Nobunaga against Asakura Yoshikage. But Azai Nagamasa has secretly decided to betray them. If surrounded by both Azai and Asakura forces, the Oda–Tokugawa alliance could be doomed. The maid Azuki heads to Kanegasaki to warn Ieyasu of the betrayal. Ieyasu notices the strange actions of the Azai forces, and urges retreat, but this provokes Nobunaga’s wrath.

Ieyasu and Tokichiro barely survive the Battle of Kanegasaki. Without pause, Nobunaga orders Ieyasu to lead the attack on the Azai and Asakura. Then a secret letter arrives from Nagamasa, urging Ieyasu to attack Nobunaga. Both armies face off across the Ane River. Ieyasu must choose whether to support or betray Nobunaga. As the debate rages, a bullet flies into Ieyasu’s camp, shot by Nobunaga!

Now based in Hamamatsu Castle, Ieyasu is attacked by a boy named Toramatsu, who says the people of Totomi hate the Tokugawa. Wounded by the words, Ieyasu seeks an alliance with Uesugi Kenshin against Shingen. But this enrages Shingen. With a decisive battle inevitable, Ieyasu rescues his brother-in-law, Gensaburo, who had been sent as hostage to the Takeda. Exactly what Shingen was hoping for!

Shingen quickly takes Tokugawa bases. Unable to retaliate, Ieyasu holes up at Hamamatsu until Nobunaga’s forces arrive. The Takeda army advances on Hamamatsu, but goes past the castle. If Ieyasu lets them through, he risks losing Totomi's people, angering Nobunaga, and endangering Sena and his family in Okazaki. Ieyasu is faced with a critical decision!

When a body in gilded armor is delivered, news of Ieyasu’s death spreads across Japan. Sena,upset, prepares for a siege. Nobunaga braces for a showdown with Shingen. Katsuyori attacks Hamamatsu Castle, Sakai Tadatsugu’s quick thinking allows the Tokugawa army to escape. As Shingen moves west, his health fails. Then, a man appears before the Tokugawa retainers.

Shingen dies, leaving everything to Katsuyori. Nobunaga expels Yoshiaki from Kyoto for siding with the Takeda. Ieyasu, still shaken by the costly battle, is comforted by the beautiful maid O-Man and gradually opens his heart to her. When Sena learns of this, she visits Hamamatsu. Their reunion stirs a complex mix of emotions.

Even after Shingen’s death, the Takeda remain strong. Katsuyori invades Tokugawa lands. Nobuyasu leads the defense with Kazumasa, but struggles. Sena and Kame tend to the wounded. Ill in Hamamatsu, Ieyasu sends Tadakatsu and new vassal Ii Toramatsu as reinforcements. Amid the chaos, a conspiracy brews within Okazaki Castle.

Nagashino Castle is surrounded by Takeda forces. Lord Okudaira Nobumasa sends Torii Suneemon to Okazaki for help. Receiving the message, Ieyasu turns to Nobunaga, who arrives with over 20,000 troops. But as a condition for aid, Nobunaga—driven by his quest to unify the land—makes a shocking demand: Ieyasu must break their alliance and serve him as a vassal.

The Tokugawa-Oda alliance faces the Takeda at Shitaragahara. But Nobunaga remains still, building stockades. Impatient, Ieyasu takes a gamble—launching a rear night attack with a small force. It works: Katsuyori charges, and that’s the moment Nobunaga was waiting for. 3,000 matchlocks fire at once, overwhelming the Takeda. Ieyasu and Nobuyasu are stunned by the brutal battlefield.

Sena’s secret meetings with Chiyo, a Takeda envoy, are exposed by Gotoku, who reports to Nobunaga. He accuses Mizuno of collusion and forces Ieyasu to punish him. After agonizing over it, Ieyasu complies and seeks comfort in the maid O-Ai. Meanwhile, Nobuyasu, shaken since Shitaragahara, hears from Sena about a dream she has long kept hidden.

Ieyasu learns that Sena and Nobuyasu sent secret letters, and that people—including Takeda allies—have been visiting Tsukiyama. If Nobunaga finds out, he could lose his beloved wife and son. In anguish, Ieyasu heads to Tsukiyama with Kazumasa. But Sena was waiting. She reveals her secret plan and pleads with Ieyasu to share her dream—but he cannot act on it.

The plan between Sena and Nobuyasu is exposed by Katsuyori, and reaches Nobunaga. If they aren’t punished, war with Nobunaga is inevitable. Ieyasu tries to deceive him and help his family escape. But Sena has Gotoku write Nobunaga a letter claiming she’s wicked, to take the blame herself. Nobuyasu, too, leaves Okazaki—refusing to run from his fate.