It’s such a pity that the more striking elements in Franz Lehár’s orchestration are heard so fleetingly, such as the tiny glints of cimbalon which give the best parts of the score an authentic bohemian - or Pontevedran - flavour. But too often the relentless parade of waltzes and polkas begins to grate, and you’re about to nod off when suddenly something ear-catching happens – a sequence of gorgeous string portamenti, a languorous violin solo, or stopped horn chords that sound as if they’ve escaped from a Mahler symphony. Then you recall that The Merry Widow was first performed in Vienna in 1905.

To paraphrase a cliché, it’s rare to leave a theatre humming the lighting. But here, Matthew Haskins’ lighting designs help make this production so powerful and evocative, whether projecting grotesque, distorted shadows on the back wall of Madeleine Boyd’s claustrophobic set, or illuminating characters’ subtle facial expressions. Dawn and dusk are both beautifully realised, and when we’re finally shown a brightly lit stage at the opera’s shocking close, you almost have to shield your eyes.

"It is a curious tale. I have it written in faded ink, a woman's hand, governess to two children, long ago..." So begins Benjamin Britten's operatic re-imagining of Henry James's ghostly chiller The Turn of the Screw. Oscar Wilde called it "a most wonderful, lurid, poisonous little tale" but how are we supposed to interpret it? In a remote country house, a governess fights to protect two children from menacing spirits. But are these spirits real or imagined?

There’s something deliciously extravagant about this Pinocchio by composer Jonathan Dove and librettist Alasdair Middleton. It’s remarkably faithful to Carlo Collodi’s picaresque text, and so we get everything. Elaborately costumed characters enter with spectacular props, then disappear having barely made their point, my favourite being the four top-hatted black rabbits who threaten to escort Pinocchio offstage in a coffin after he’s refused to take his medicine.

Ever since I can remember, the composer Mieczyslaw Weinberg has played a walk-on part in histories of Soviet music. If you find him in an index at all (probably under Vainberg or Vajnberg, and usually with the first name given him by a box-ticking Soviet border guard in 1939: Moisey, or even Moshe), you’ll usually end up reading one of those melancholy and unhelpful lists: “Shostakovich’s followers include...”

A thousand miles away from the Disney version, the transformation scene in Dvořák’s Rusalka is bleak and terrifying. With not a cauldron, bat or cobweb to be seen, the heroine is strapped to an operating table before imbibing the witch’s magic potion intravenously. Then her legs, until now swaddled together, are literally torn apart. It’s a brutal, shocking moment; no surprise that some audience members giggled nervously.