There was an air of muted celebration in the packed theatre. You might not have known this is Richard Alston Dance Company's final tour, except that every curtain call was a little bit longer: we were inclined to clap. So much so that in one piece we clapped each movement. Having started, we didn't want to leave any combination of dancers out.

We started with Red Run from 1998, making it nearly as old as some of the audience. A challenging soundtrack of tortured bass strings by Heiner Goebbels underscored jerky, sketchy movements, on a stage flooded with red light. In the last section Ellen Yilma lamented through waterfall glissandos.

Next came associate choreographer Martin Lawrance's brand new A Far Cry. Danced to some cheery Elgar, the glorious punchiness of the dance gave the dancers grace and freedom. I've never seen a piece of choreography so perfectly matched with its music. The dancers seemed to embody the line and phrase, every twirl, trill, cadence and nadir perfectly aligned 'til you couldn't tell what created what. It was breathtaking.

In the middle section, Alston's charming Mazur from 2015 lilted us. Jason Ridgway played Chopin's music live in the corner of the stage, making the space more intimate, as Joshua Harriette and Nicholas Shikkis, in shirtsleeves and waistcoats like hipsters on a day off, playfully interacted. Shikkis's long expressive arms tangled into the music. It wasn't a romantic pas de deux, just two friends on a journey.

The grand finale came in the form of Alston's new Voices and Light Footsteps, his swansong for the company, to the stately but intricate music of Monteverdi. We saw most combinations of dancers through the 10 movements of the piece, sometimes Monique Jonas' catlike sinuous grace, sometimes the whole company roaring across the stage as if chasing away an invader. The dancing was more formal and balletic, but still without the rigid strictures of classical ballet. The women were dressed in complementary colours of satin, from white through yellow and copper to red. They shimmered (though my companion and I both hated the cowl neckline, which bounced distractingly).

Inhabiting a world of words, I always worry before a dance performance whether I'll understand what is being conveyed; whether I'll "get it". When an artform could at any moment have the players depicting characters, the line, the narrative itself - how can we hope to untangle that? And yet the miracle is that it always works. You can like some pieces more than others, but they all tell you something. Sadly, Richard Alston won't be telling us anything more through the medium of his company. But talk about leaving on a high.

Richard Alston celebrates his 50^th year of making dance with a show that starts deliciously hard and uncompromisingly modern.

Detour, a new work by choreographer Martin Lawrance, opens with sparkling glockenspiel, layers up into hypnotic layered percussion reminiscent of helicopters, hurricanes, machinery, modernity. The music is Michael Gordon’s Timber remixed by Icelandic composer Jóhann Jóhannsson, performed by Mantra Percussion, and these dizzying layers of complexity translate into a steely choreography that is fast and complicated, yet wintry and sparse.

The dancers wear simple drapes in building-site colours, spin like sycamore seeds, jump and crouch like concrete gargoyles, and finally wind the action up in dazzling, complicated style, spinning like cranes on the bleakly sparse stage. Quartermark, a cheerful ruffle through Alston’s rich back catalogue, starts with stunning solos from Monique Jonas and Joshua Harriette, languid and liquid explorations of longing and loneliness, at times in almost chiaroscuro darkness.

Bach Dances pairs utterly familiar music with a dislocating marionette tag-team dance. Finally, Signal of a Shake brings the whole company back onstage for some millennial magic in this optimistic, uplifting piece set to the mighty organ music of Handel.

A pause for applause, and then the almighty Proverb arrives, set to the Steve Reich vocal piece of the same name. Sharp contemporary shapes and colours jut across the stage, interrupted by splashes and shadows of deepest black; twitches of movement leap through the dancers, who swing and turn like a mid-century modern mobile. It is hypnotic, mesmerising, utterly beautiful, with elegant duets from Jason Tucker and Carmine De Amicis, among others.

The evening ends on Brahms Hungarian, a cheerfully indulgent pirouette of a piece with live piano from Jason Ridgeway, boho waistcoats, floaty dresses and plenty of fun for the dancers, who zip and skip their way to a happy finale.