Mark Gatiss as the Captain and Peter Capaldi as the Doctor in "Doctor Who" Christmas Special "Twice Upon a Time"
Mark Gatiss as the Captain and Peter Capaldi as the Doctor in "Doctor Who" Christmas Special "Twice Upon a Time" BBC

The “Doctor Who” Christmas Special was an exciting episode for both classic and new Whovians, but not everyone was happy about it. The episode, in which Peter Capaldi’s Twelve was seen regenerating into Jodie Whittaker’s Thirteen, could be the subject of a legal action after it mentioned one of its classic characters.

Spoilers for the most recent episode of “Doctor Who” are included below. The episode aired in Australia on Dec. 26.

In “Twice Upon a Time,” a weakened Twelve wandered through the South Pole outside his TARDIS, refusing to regenerate. He then encountered his first incarnation, the First Doctor (guest star David Bradley), who was also wandering outside his TARDIS and also refusing to regenerate. They then encountered a First World War British captain (guest star Mark Gatiss), who was displaced from December 1914 while in a war.

The Captain’s name was later revealed to be Archibald Hamish Lethbridge-Stewart, who fans quickly and correctly assumed to be the grandfather of Brigadier Alistair Gordon Lethbridge-Stewart. The Brigadier was one of the Doctor’s most faithful companions throughout the years.

The estate of one of the Brigadier’s creators wasn’t too happy about the appearance of the Brigadier’s progeny, though. The character was co-created by Mervyn Haisman, and his estate is now considering legal action.

“Characters are considered creative works and are protected by copyright law,” Andy Frankham-Allen, creative director of the Haisman Estate, was quoted by the Mirror as saying. “As such, we reserve the right to determine what is officially part of our intellectual property. If derivative works are created without our permission, then we will determine if/how they fit into our IP. We reserve the right to accept or reject any additions to our intellectual properties.”

A BBC spokesman insisted that the claim was “without foundation,” saying they did not breach copyright.

The Brig first appeared in the 1968 episode “The Web of Fear.” He was first a companion to the Second Doctor (Patrick Troughton) and then became a more frequent companion and friend to the Third Doctor (Jon Pertwee). He had worked with almost every Classic Doctor in the series.

Meanwhile, Whitaker, who has replaced Capaldi for the title character, revealed she had no idea what would happen in the Christmas Special episode, save for the bit where she was introduced. She told Doctor Who magazine that she did not read the rest of the episode because she was only given one page of the script, which was when Capaldi regenerated to her.

She also revealed how she came up with the colours of her character’s costume. “The first meeting I had about the costume was all very secret,” she said. “As we were talking, I was distracted by the colour of the wallpaper behind us. I told Ray [Holman, costume maker] I loved it – and that’s the colour of the trousers.”

Jodie Whittaker as the new Doctor Who
Jodie Whittaker as the new Doctor Who BBC