Can a 31-year-old cool kid bring France’s oldest couture house back to its former glory? That is the task the designer Bruno Sialelli is faced with at the French fashion house Lanvin and on Wednesday morning all eyes were on his debut.

It’s not an easy task for a young designer who is used to being behind the scenes to take the spotlight, not least at a house which has been in turmoil since the acrimonious departure of its much-loved and revered creative director Alber Elbaz in 2015. Amid staff revolts and sporadic changes in strategy from the then owner, Shaw-Lan Wang, in the three-and-a-half years that have passed the house has seen two designers – Bouchra Jarrar and Olivier Lapidus – hurriedly appointed before being swiftly shown the door.

As a result, the industry is pinning its hopes on Sialelli not only delivering a collection of hits but reigniting the reciprocal love affair they enjoyed. If he was nervous about his big moment he didn’t show it. While admitting it was an emotional moment, he said after the show that he was focused on “redefining the wardrobe” of the house and to do so he visited the personal archive of the house’s founder, Jeanne Lanvin.

Sialelli visited the personal archive of the house’s founder, Jeanne Lanvin, for inspiration. Photograph: Stéphane Mahé/Reuters

This was not, however, a trip down memory lane, but a fresh reinvention of the house’s history, which informed but did not dictate.

Sialelli said he was instinctively drawn to the brand’s famous Lanvin blue, which he presented in modern knitwear that took the form of a cardigan-dress hybrid, pea coats with scalloped lapels and blue ribbed tabards.

The latter was part of the overriding medieval theme of the show. Sialelli revealed Lanvin herself frequently worked with motifs from the era and he reintroduced it in scarf prints and – poignantly – an appliquéd motif of a knight in shining armour, a clever nod to Sialelli’s own crusade.

He also worked Aztec and Fairisle patterned blankets into inserts on coats as wind-flaps and cuffs. Lanvin was a prolific traveller, he explained, “always bringing back the most beautiful fabrics” from her trips around the world.

Following in former creative director Albert Elbaz’s shoes, Sialelli created fun and mischievous pieces for this collection. Photograph: Stéphane Mahé/Reuters

Refreshingly, Sialelli injected a sense of fun and mischief to the house that Elbaz delivered in bucketloads but which has been absent during his successors’ tenures. Illustrations from Jean de Brunhoff’s Babar the Elephant books appeared on silk shirts and bomber jackets, while a fox motif was 3D-appliquéd on lace slips, and hemlines came with click-clacky Perspex embellishment.

He staged the show in the Musée de Cluny, installing vases of black tulips beside Pierre de Montreuil’s 13th century statue of Adam, signalling an important detail of the lifestyle direction Sialelli wants Lanvin to take. “Jeanne Lanvin was a lifestyle woman – she started very early to do menswear, womenswear, sportswear, furniture and I think it’s still very valid. There is a legitimacy for the house to propose a valued range of projects [and I] wanted to somehow initiate the house’s lifestyle vision.”

Sialelli worked for four years under JW Anderson at Loewe – aka the poster brand for blending art, culture, and fashion – before his appointment at Lanvin, and it is clear he wants to bring that spirit with him.

Before that he was in the design team at Balenciaga where he navigated the transition between the head designers Alexander Wang and Nicolas Ghesquière in 2015, suggesting that he has understanding of the upheaval the long-time atelier team at Lanvin have been through.

Before taking the reigns of Lanvin’s creative process, Sialelli worked for JW Anderson and Balenciaga. Photograph: Stéphane Mahé/Reuters

In February 2018, the private Chinese conglomerate Fosun International, controlled by the billionaire businessman Guo Guangchang, fought off the competition to become majority shareholders in the business, leaving Wang with a minority stake. While details of the deal were undisclosed, the group is said to have injected a minimum of €100m (£85m) into the brand to help mop up inherited issues and kick-start the house into a new trajectory.

On Wednesday, the show notes said Sialelli was “sublimating the illustrious heritage of the French maison in the midst of its own renaissance” and judging from this first collection, Lanvin looks like it’s finally found the man for the job.