The Secret of Calligraphy ..., is perhaps, together with Chushingura, the most popular play of the Kabuki theater. Mainly written by Takeda Izumo (1691-1756), the successor of Chikamatsu as playwright for the Takemoto Theater in Osaka, with the collaboration of Miyoshi Shoraku, Namiki Senryu and Koizumo, it was performed by the first time in 1746. 

The play is based in the story of the misfortunes of Sugawara-no-Michizane (843-903), who become chancellor to the Emperor Daigo. After being falsely accused of treason, he was banished to Tsukushi, where he died in poverty. 

Sadanobu:

The central theme of the plot is the vengeance carried out by three brothers (Matsuomaru - Pine, Umeomaru - Plum and Sakuramaru - Cherry), sons to a servant of Michizane, their godfather. The climax of the play is the sacrifice made by Matsuomaru, who sacrificed his own son to save the life of Kanshusai, son of  Michizane, and thus preventing the extinction of the Sugawara line.