The play Kagamiyama sugata no utsushi-e (A true picture likeness at Mirror Mountain: 鏡山姿写絵) premiered with the performance depicted in Hirosada's diptych. It is related to a group of Kagamiyama mono (Kaga Mountain Plays: 加賀見山物) both from the puppet and kabuki theaters that were adapted from the ningyô jôruri (puppet play: 人形淨瑠璃) Kagamiyama kokyô no nishiki-e (A brocade picture of the birthplace at Mirror Mountain: 鏡山舊錦絵), premiering in Edo, 1782. These plays dramatized eighteenth-century rivalries within the Maeda clan in Kaga.
A slightly earlier Kyoto production was Kagamiyama kuruwa no kikigaku (A picture of the pleasure quarter at Mirror Mountain: 鏡山廓の写本) premiering in 1780. One of the better known Edo adaptations was Keisei Soga kuruwa Kagamiyama (Mirror Mountain and courtesan's Soga in the pleasure quarters: けいせい曽我廓鏡山), a play about two courtesans in the Yoshiwara, Edo.
The main plot line (not depicted here) was based on a real-life incident from 1724 when at the Edo palace of Lord Matsudaira of Suo, the maidservant Osatsu avenged the death of her mistress, Omichi, who had been driven to suicide after being struck by a sandal — considered a terrible insult — by a woman named Sawano. In typical fashion, theatrical adaptations changed the names of the protagonists. After the lady-in-waiting Onoe uncovers a plot to seize power from the shogun by an court woman named Iwafuji, the latter insults Onoe by striking her with a sandal. Onoe commits suicide, but only after revealing the conspiracy to her maid, Ohatsu. The dutiful maid foils the intrigue and kills Iwafuji with a sword, then symbolically beats the corpse with Onoe’s blood-stained sandal.
In the present play Kagamiyama sugata no utsushi-e, the Kaga clan name has been changed to Taga, hence the role Taga no Taishu. The role of Torii Matasuke originally appeared in the Kyoto-based play Kagamiyama sato no kikigaki (1780), written by Nagawa Kamesuke (died 1790). The scene shown here, once part of the original play, is no longer performed. It included an armed confrontation between Torii Matasuke and a lord named Taga. The two meet at the river's edge, Taga riding a black war horse in the fast-flowing current and Matasuke poised for action. The mie ("display" or dramatic pose: 見得) of the two actors must have thrilled kabuki audiences of the period, with Matasuke gripping his wakizashi (short sword: 脇差) and Lord Taga ready to match Matasuke's ferocity. Later in the play Matasuke sacrifices himself and then, at the climax, returns as a vengeful spirit to defeat his enemies.
This is certainly one of Hirosada's more dramatic designs. The roiling river with its Hokusai-like cresting waves, along with Taga's aggressive gesture of the raised sword and the rearing up of his caparisoned steed, animate the composition and capture a thrilling moment from the play.
References: WAS-VI, no. 6-316; KNP-6, p. 564; IKB-I, p. 105, 2-516; NKE, pp. 250-252