If you dropped in on the middle act of Dvořák’s Rusalka, in its current production at the Lyric, you would be confronted with the strange fact that the opera’s heroine, the eponymous water nymph-turned-human, barely sings at all. Instead, there is a grand hall, full of people who chat, sing and dance. The ballet numbers, exquisite in this production, take on an edge of cruelty in the face of Rusalka’s gagging: they emphasize the opera’s silent heart.

Rusalka has made the familiar bargain that is hardly a bargain at all: she is transformed into a human so as to better woo the prince she loves, but at the cost of her voice. For an opera character, it is nearly a death sentence. Luckily, Ana María Martínez, who plays the title role, has rich opportunities in the first and third acts to show us her considerable abilities. She sings with a directness of feeling that is only occasionally stiffened by the positions the directors put her in; for instance, splayed out on a bough under the moon, they flip her around like an omelette. The way she lies under the moonlight bears a strong comparison to a moment in Lars von Trier’s recent film Melancholia, in which Kirsten Dunst lies in a similar position while opera (Wagner, in that case) swells below, a visual resonance which solidified for me when hands began thrusting through the twisted vines - an image from von Trier’s Antichrist.

The human world is more of an Eyes Wide Shut, with its erotic formality and sheen of civility. The stage space is used excellently in the second act, restricted to a vertical slice as we first peer into the kitchens, animal carcasses strung up in an overt gesture of humankind’s attitude toward nature; then more expansively to reveal the dozens of stag trophies lining the walls of a gorgeous foyer. With Martínez mostly out of the picture, it is up to Eric Owens as Vodník, Rusalka’s water goblin father, and Brandon Jovanovich, her prince, to shine, which they do. In his daughter’s escape into the human world, Vodník suffers not only the loss of his child but also her rejection of his way of life, the home he has made for her; you can hear the heartbreak in the crack of Owens’ voice.

Jovanovich is just the tenor for this melodrama, marrying exquisitely with Dvořák’s Wagnerian tinged melodic lines. The production, from director Sir David McVicar and set designer John Macfarlane, is an achievement of pacing and deep understanding of the ways in which stage space can be built up, blocked off, and opened up. I liked the surreal silliness of a copse of trees swaying in the moonlight, as well as the formal effect of that copse moving aside to reveal the night sky. I could have done without the sexual cavorting of the wood nymphs; their gyrating reveals nothing except for a timidity about sex. Far better to focus on the love between the water nymph and the prince, which is here rendered so sincerely that you can’t help being moved.