Buxton's double bill brings together two rarities: Sibelius's only completed opera, The Maiden in the Tower, from 1896, and Rimsky-Korsakov's late one-acter Kashchei the Immortal, premiered in 1902. Both are sung in Rodney Blumer's clear English translations. Working with the same cast of five in each, director Stephen Lawless stresses some striking narrative similarities by treating the two operas as a sequence, with the characters in the first transmuting into those of the second.

Both these essentially fairytale pieces prove worthwhile. Sibelius's opera has a romantic medieval setting that Lawless and designer Russell Craig update to the period of the work's composition. They move it to a children's nursery, where the bullying bailiff's son shuts a young girl up in a turreted doll's house, whence she is eventually rescued by her lover. Lawless's absurdist approach is deliberately disturbing, working simultaneously with and against the grand-scale emotions of a score in which the composer's Wagnerian heritage is still evident.

For its original audiences, Kashchei had more directly political resonances: the evil wizard's imprisonment of the princess emblemised Tsarist oppression, her rescue by young Prince Ivan the kind of political change liberals such as Rimsky-Korsakov wanted to see. More darkly fantastical in its use of theatrical expressionism, Lawless's production matches the score's vividly virtuosic writing, which is wonderfully presented by the Northern Chamber Orchestra under Stuart Stratford.

The cast work hard in both pieces, hurling themselves at consistently challenging vocal writing. Richard Berkeley-Steele is at his best as the demonic Kashchei, while Owen Gilhooly turns effortlessly from the villain of the first opera to the hero of the second.