Games Workshop is hoping to replicate the success of hit fantasy TV shows such as The Witcher with a new series based on its Warhammer 40,000 tabletop game.

As the high-street fantasy-figure seller’s shares hit an all-time high, the company said a series based on the Eisenhorn books, set in the game’s dystopian universe, was in development. The novels follow the adventures of the Imperial Inquisitor Gregor Eisenhorn as he scours the galaxy for heretics and demons.

The Games Workshop chief executive, Kevin Rountree, said work on the show was progressing well as the company reported record half-year sales and profits.

“No production contracts have been signed yet,” he said. “Our experts continue to work with our external partners learning how this industry works to ensure, if it does go into production, our first TV show is not only true to our IP but is a commercial success too.”

The update came as the retailer bucked the high street gloom with year-on-year sales up 16% to £145.6m in the six months to 1 December. Sales last month were “in line” with expectations, the company added. Pre-tax profits jumped 44% to £58.6m, sending the shares up 9% to £69.60 on Tuesday, valuing the group at close to £2.3bn.

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The Nottingham retailer and model manufacturer has been a sleeper success story with its shares more than doubling in the past year as its Warhammer franchise goes from strength to strength. The number of people logging on to Warhammer-community.com was up 48% in the period, with fans returning to the site more frequently.

“Our business and the Warhammer hobby continue to be in great shape,” Rountree said. “We are pleased to once again report record sales and profit levels in the period. The global team have worked their socks off to deliver these great results.”

He also pointed to the success of its new Citadel Colours paint range, which comes in shades such as “ork flesh” and “blood angels red”. The company had delivered a step change in its paint offering, Rountree said.