Mark Gatiss has dismissed rumours that the next instalment of Sherlock will be a one-off special, after Martin Freeman implied the show could return for a single film.

Speaking at the TV Baftas, Gatiss said that a fourth series was still “the plan”, adding that the production team were moving closer to agreeing dates for filming the forthcoming season.

“There was talk [of a single film, but] amongst people who have nothing do with Sherlock, I’m afraid,” he told RadioTimes.com.

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Creator Steven Moffat confirmed earlier this year that Sherlock will return for a fourth and maybe even a fifth series, adding that he and Gatiss had started plotting future storylines.

Shape Created with Sketch. Sherlock series three in pictures Show all 17 left Created with Sketch. right Created with Sketch. Shape Created with Sketch. Sherlock series three in pictures 1/17 Sherlock series three Martin Freeman as Dr John Watson and Benedict Cumberbatch as Sherlock Holmes BBC 2/17 Sherlock series three Sherlock gives his unforgettable best man speech 3/17 Sherlock series three Martin Freeman and Benedict Cumberbatch in Sherlock BBC 4/17 Sherlock series three Una Stubbs as Mrs Hudson BBC 5/17 Sherlock series three Martin Freeman as Dr John Watson BBC 6/17 Sherlock series three Newspaper proprietor Charles Augustus Magnussen makes Lady Smallwood an offer she can't refuse BBC 7/17 Sherlock series three Lars Mikkelsen as the newspaper proprietor Charles Augustus Magnussen BBC 8/17 Sherlock series three Lindsay Duncan as Lady Smallwood in Sherlock BBC 9/17 Sherlock series three John and Mary get married while Sherlock looks on BBC 10/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 11/17 Sherlock series three Mark Gatiss as Mycroft Holmes BBC 12/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 13/17 Sherlock series three Louise Brealey as Molly BBC 14/17 Sherlock series three Rupert Graves as DI Lestrade BBC 15/17 Sherlock series three Martin Freeman as Dr John Watson BBC 16/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 17/17 Sherlock series three Amanda Abbington as Mary Morstan BBV 1/17 Sherlock series three Martin Freeman as Dr John Watson and Benedict Cumberbatch as Sherlock Holmes BBC 2/17 Sherlock series three Sherlock gives his unforgettable best man speech 3/17 Sherlock series three Martin Freeman and Benedict Cumberbatch in Sherlock BBC 4/17 Sherlock series three Una Stubbs as Mrs Hudson BBC 5/17 Sherlock series three Martin Freeman as Dr John Watson BBC 6/17 Sherlock series three Newspaper proprietor Charles Augustus Magnussen makes Lady Smallwood an offer she can't refuse BBC 7/17 Sherlock series three Lars Mikkelsen as the newspaper proprietor Charles Augustus Magnussen BBC 8/17 Sherlock series three Lindsay Duncan as Lady Smallwood in Sherlock BBC 9/17 Sherlock series three John and Mary get married while Sherlock looks on BBC 10/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 11/17 Sherlock series three Mark Gatiss as Mycroft Holmes BBC 12/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 13/17 Sherlock series three Louise Brealey as Molly BBC 14/17 Sherlock series three Rupert Graves as DI Lestrade BBC 15/17 Sherlock series three Martin Freeman as Dr John Watson BBC 16/17 Sherlock series three Benedict Cumberbatch as Holmes BBC 17/17 Sherlock series three Amanda Abbington as Mary Morstan BBV

He said in January: “Rather excitingly, Mark and I, for no particular reason, just started plotting out what we could do in the future. We plotted out the whole of series four and five. The ideas we had that day, I thought were the best we’ve ever had.”

Production dates for the fourth series are said to be difficult to confirm due to Benedict Cumberbatch and Martin Freeman's busy acting schedules.

Freeman has confirmed to star on the London stage as Richard III this autumn, while Cumberbatch is due to star in forthcoming biopic Flying Horse, about pioneering photographer Eadweard Muybridge.