For many days Hosshō (waki), a high priest from Enryaku Temple in Mount Hiei, has been maintaining a holy fire and praying for world peace. Today is the last day of the sacred ritual. He is chanting the Niō sutra as his final rite, when he hears knocking on the gate. Although Hosshō considers it strange for a visitor to come at night, he opens the door. Before him stands the ghost of the late Sugawara Michizane (shite of act one). Happy to be reunited with his student, Hosshō welcomes him inside. Michizane expresses his gratitude for Hosshō's kindness while he was alive and declares that the relationship between teacher and student is the noblest of all.
After exchanging civilities for a while, the ghost of Michizane reveals his plan to become a Thunder God, go to the Imperial Palace and wreak vengeance upon all that have wronged him in his lifetime. He asks Hosshō not to go to the capital even if he is summoned by the court. Hosshō understands, but replies that if the court insists on his presence, he will not be able to refuse. Upon hearing that, Michizane's face transforms into that of a demon. He takes the pomegranate that has been offered at the altar, crushes it with his teeth and spits out flames towards the gate.
Hosshō quickly chants magic incantations. The flames eventually dissipate and Michizane's ghost disappears along with them.
The scene shifts to the Imperial Court. As Hosshō is fervently praying, the God of Thunder (shite of act two) appears. Thunders echo around the Imperial Palace and the whole building starts shaking. However, the lightnings are unable to reach Hosshō. The Thunder God and Hosshō engage in an exhausting battle. Hosshō recites various Buddhist sutras. Eventually, the Thunder God's strength is depleted, he climbs onto a black cloud and flies away.
This Noh play is based on one of the legends about Sugawara Michizane. Since an early age, Michizane displayed great abilities and even made his way to the position of Minister on the Right. However, a courtier called Fujiwara Tokihira brought him down through a clever plot and exiled him to Dazaifu, where he soon died. It is believed that after his death, Michizane's vengeful spirit returned to the Imperial Court to curse and kill Tokihira and his allies and, through various natural disasters, wreak havoc on the capital. Those who feared the spirit of Michizane later started venerating him as the god Tenjin.
This legend can be seen in many works of literature such as "Taihei-ki" and was very popular with the masses. It was eventually skilfully depicted in the play "Raiden".
The first half of the play revolves around the ghost of Michizane appearing before Hosshō to express his gratitude for Hosshō's mentoring him while he was alive. Although based on the popular legend, it depicts the relationship between teacher and student more vividly than any version of the story seen in other works of literature. The deep gratitude Michizane has for his mentor can be perceived in the second act, when the God of Thunder casts lightnings everywhere except upon the praying Hosshō.
At the end of the first act, the otherwise calm and reasonable Michizane rapidly flies into a rage. The movements of the shite actor become violent and energetic in accordance with the fast change of tempo in the choir's singing.
In the second act, Hosshō and Michizane, master and student, engage in a fight. The two platforms on the stage represent the buildings of the Imperial Palace. Both actors skilfully use the platforms to visualise the fierce battle and stamp on them to create the effect of rolling thunder. The style of the play allows the audience to enjoy it not only visually, but also aurally.