A secret collaboration by two elder statesmen of style – one who dresses Michelle Obama, the other a favourite of Edina Monsoon from Absolutely Fabulous – has taken the Paris catwalk by storm.

Dries Van Noten, 61, founded his label in 1986 and has been a cornerstone of fashion week in Paris ever since. His vibrantly coloured, intricately detailed but always wearable clothes have earned him a devoted customer base who have kept him afloat through the vagaries of trends. Christian Lacroix, 68, founded his fashion house one year later, in 1987. His star burned brightly for two decades in which his flamboyant dresses starred on red carpets and magazine covers, until losses forced him to shutter the house in 2009.

Christian Lacroix no longer owns his trademark, and his name has not appeared at fashion week for a decade. The first hint that Dries Van Noten’s show was to be out of the ordinary was the red rose that had been placed on each seat, with a ribbon tag signed DVN*XCLX.

Back when Christian Lacroix staged fashion shows, the audience would throw roses on to the catwalk when he made his bow during the finale, a ritual taken from the bullfights of Lacroix’s native Arles. The setting for this show was straight out of Van Noten’s understated playbook – a minimalist, poured-concrete space at the modernist Opera Bastille – but when the first model appeared, she wore in her hair a large black feather, another tradition remembered from Lacroix’s own fashion shows.

On the catwalk at the Dries Van Noten spring/summer 2020 women’s ready-to-wear collection. Photograph: Benoît Tessier/Reuters

Polka dots were followed by flamenco ruffles, and then a chartreuse opera coat gathered with festoon swagging. There were fuchsia taffeta trousers with waterfall hems. By the time exit 41 appeared – a blood-red matador jacket with gold embroidery – the closely guarded secret of a co-collection was becoming clear. The two men took their bow together at the end of the show.

Van Noten said of the collaboration that he had found himself “needing exuberance, opulence, another volume and fun”.

“I was constantly drawn to the 80s and 90s, to a love of dressing up, to couture, to beauty, to audacity – to joy. I quickly realised that all roads seemed to lead to the work and world - of Mr Christian Lacroix. So I thought why not just phone him, why not phone Christian and ask if he would be up for the challenge and enjoy working with me on a collection. I was so happy when he immediately said yes.”

The two designers, who have spent the past five months working together, stood shoulder to shoulder as they accepted congratulations and posed for photos with their arms around each other. Christian Lacroix, who has had a successful career designing for the opera and ballet in the decade since his last haute couture show, was visibly emotional to be back in the fashion throng.

The Dries van Noten ready to wear SS20 collection. Photograph: François Mori/AP

The cloak-and-dagger secrecy and the surprise “drop” of the collection was a smart trick. Van Noten and Lacroix won the news cycle of fashion week and the stunt ensured that this collaboration will resonate on the social media feeds of millennials for whom the 20th-century glory days of Lacroix are ancient history. And by having the first few outfits pass as Van Noten before the realisation occurred to most of those in the audience, the show illustrated how surprisingly close Van Noten’s more cerebral, Belgian-trained aesthetic is to Lacroix’s flamboyant, Mediterranean-facing maximalism. In their painterly sense of colour and passion for drama in fashion, they are kindred spirits. The collaboration, which is understood to be a one-off for this season, was a celebration of “mutual admiration”, Van Noten’s spokesman said.