It’s opera’s oldest riddle: what comes first, words or music? The answer is usually “Music, of course” but opera without a story and the words to tell it is meagre stuff indeed.

The reign of Elizabeth I has provided opera with stories aplenty. The latest piece to mine this rich narrative vein is Philip Cashian’s The Cumnor Affair, described as “an Elizabethan murder mystery”. The Earl of Leicester, Elizabeth’s favourite courtier, is inconveniently married to Amy Robsart. When she dies in dubious circumstances, Leicester has to choose between fidelity to his wife’ s memory and devotion to his queen. Sundry plotters render the choice impossible.

Iain Pears’s libretto tells the story conversationally but not too plainly, and Cashian’s music responds with no little vigour. Much of the character is within the tiny orchestra (in this instance, Chroma, half-visible throughout), with wind instruments carrying the mystery, percussion the menace. If the voices aren’t always as colourful, perhaps Cashian’s writing for them is just too even, too plainly syllabic.

Still, there are moments when passions fly, especially when Amy Carson reveals the wronged woman’s broken heart. Her voice, although slightly pinched at the top, carries a wealth of feeling. Elizabeth herself (Sibylla Melenberg) is an eerie presence, saying nothing but observing everything from within a gilt frame above the stage. Smaller roles are well taken, and if Bill Bankes-Jones’s production for Tête á Tête doesn’t quite make a virtue out of its low budget, it delivers the action clearly enough.

Until Sunday (020 8237 1111).