Fans of the "Impossible Girl" Clara Oswald should not miss the next "Doctor Who" episode, because it just may be her last.

There is no news yet as to what tragedy will befall on Jenna Coleman's Clara, but according to the Twelfth Doctor Peter Capaldi, it may come sooner than we think.

Radio Times reported that at a recording of the Graham Norton Show (episode to be released on November 20), Capaldi spoke about this week's episode, saying, "It's a sad one, gripping and very strange."

He added, "And it's the end of the line for Clara Oswald played by Jenna Coleman who's been my companion for the last two years. It's the end of her story. I don't want to go into the details of it, but it's sad."

When asked about Clara's return in the future, he shared, "Sometimes people can't come back. Sometimes things happen that they can't come back from."

Fans know that Jenna Coleman is leaving soon, but is it as soon as the next episode? It would seem so, if her goodbye to the Doctor in the episode trailer is for real. But then again, it could also be a bluff.

Capaldi's words seem to mean that it is goodbye though, as he spoke of Coleman with a sense of finality. Wales Online shared more details of the recording, with a seemingly sentimental Capaldi saying, "She was there at the beginning and showed me around the Tardis and showed me the ropes. 'Doctor Who' is a wonderful show but it is a big juggernaut and it's nice to have someone who has already been there for a few years to compare notes with when things get a bit rough."

The Doctor's new assistant as of late is "Game of Thrones" actress Maisie Williams, who has guest-starred in the series and took Capaldi's breath away, in terms of her acting, of course.

Capaldi calls Maisie "fantastic" and "lovely," recalling her entry in the HBO series at the age of 12. He cites doing a scene with her, when the latter "pulled" him back as he was in her light.

On another note, if Jenna Coleman is really leaving, it means that there is a slot for the Doctor's companion, and with Williams still in contract as Arya Stark in the massively successful HBO fantasy drama, it is highly unlikely that she can go on "Doctor Who" full time, no matter how fond Capaldi has become of her.

Do you have any ideas as to who will take Clara Oswald's place in the Tardis?