Hansel and Gretel, Pop-Up Opera review - salty-sweet production takes wry pleasure in classic fairytale

They’ve done it in a boat and a barn, a former poorhouse and even a tunnel shaft, and now Pop-Up Opera bring their latest production to a museum. Bethnal Green’s 19^th-century Museum of Childhood provides an evocative frame for Engelbert Humperdinck’s Hansel and Gretel, its glass display cases and carefully glossed and labelled toys setting the tone for a production that takes a wry, curatorial approach to its material.

This knowing, arch quality to the drama comes almost entirely from Harry Percival’s surtitles, or “captions” as they are more accurately termed in the programme. Freely paraphrased or summarised, and overloaded with insistently up-to-the-minute slang and cultural references (Brexit, Strictly, McDonalds) they are determined to pull the rug from under every moment of onstage sincerity. Their look-at-me, larky humour soon begins to chafe against the passionate conviction and commitment of James Hurley’s young cast, whose actions need no ironic commentary to be thoroughly engrossing.

Gurning and grinning, greedily munching down the Witch’s sweets and play-fighting with Gretel, Polly Leech’s Hansel (pictured below with Sofia Larsson a Gretel) is a joyous thing indeed, an Octavian in the making. Endlessly game and completely at ease, Leech is a natural clown and a wonderfully warm presence, whose lovely even mezzo already opens out at the top into something really exciting. It’s Leech that anchors the brother-sister partnership, a dynamic foil to Sofia Larsson’s quieter, sweeter Gretel, whose music comes in and out of focus in this tricky space.Hurley’s efficient contemporary production relies on its children to imagine us into Humperdinck’s fairy-tale fantasy. A fridge, assorted mops and buckets and some cardboard boxes offer an unpromising set of tools, but the cast conjure plenty of magic from them: mops become broomsticks or trees in the dark forest, strips of cardboard a songbird.

The arrival of a splendid gingerbread house in Act Three - delivered courtesy of “Due Fairy” (groan) Rebecca Moon - ups the ante just when the action needs it, and Ailsa Mainwaring fills it with character as a pinny-clad Witch. Both she and Father (James Harrison) tread a careful line between near-tragedy (there’s an almost Wozzeck­-like edge to their domestic scene, powerfully sung) and broad comedy, giving the tale the dangerous edge it needs if it’s not to get too cutesy-kitsch.

The vast, double-height atrium of the museum (built originally to house displays from the Great Exhibition of 1851) makes for a generous, if slightly boomy, acoustic – miraculous for the cuckoo calls and echoes of the forest, which trill magically from the gallery high above, but less ideal for the balance between resonant grand piano and singers. If pianist Berrak Dyer occasionally overcooks her accompaniment, the singers wisely keep things more contained, working with rather than against the generous space to deliver a performance that leaves rival fringe companies in their icing-sugar dust.

• Pop-Up Opera's Hansel & Gretel tours until 19 November
• Read more opera reviews on theartsdesk