Real "Doctor Who" fans know that nothing is permanent on the show, which is why they are no longer surprised that a lot of changes are coming in season 10.

With just three episodes left for season 9, "Doctor Who" will have to bid goodbye to the Time Lord's present companion Clara Oswald since actress Jenna Coleman will no longer return for another installment of the iconic British sci-fi series. This left fans wondering who will replace Coleman and how Clara's departure will affect the series.

The answers were explained in a recent interview with series showrunner Steven Moffat and lead star Peter Capaldi with Digital Spy.

According to Moffat, the new Time Lord companion will be nothing like the ones before, and the character will somehow change the dynamics of the series even if she, or he, has no name yet.

"The kind of person we are going to find and how that's going to change and inflect the show. That's even before we have a name for that person, so it's really quite early stages," Moffat explained.

Capaldi, meanwhil, revealed that Doctor Who will have a hard time dealing with Clara's departure in the upcoming installment of the series. "It's thrown him," Capaldi shared. Moffat reiterated the actor's statement, saying that "It's going to knock him [Doctor Who] for six. I mean, it always does. It always half kills him, I think, but it's going to be pretty bad this time."

When asked if there is a chance that there could be more than one companion for "Doctor Who" next season, the series showrunner only provided an indirect answer. "Anything is possible, there is no set formula for this at all," Moffat said.