Right up to the moment it was broadcast on Christmas day, ‘Twice Upon A Time‘ was subject to all sorts of rumors dealing with everything from the recreation of Hartnell-era footage to cameos by former companions. Ultimately, many of those were proven true to one extent or another (some scenes from ‘The Tenth Planet’ were recreated – though not as many as rumored – and each of Capaldi’s former companions made an appearance), though one of them – the appearance by Jenna Coleman – very nearly didn’t.

No, she doesn’t have any bad blood with the production office. Nor does the former companion share Christopher Eccleston‘s infamous reticence to revisit past roles. Rather, her commitment to ITV’s ‘Victoria’ keeps her more than a little busy, as the special’s director Rachel Talalay explains:

“It would have been such a loss if Jenna hadn’t been able to appear. God knows she’s busy. This wasn’t like “I don’t want to do it.” This was like “I’m the star of a huge show and you’re asking me to find time to come do this.”

Even then, it was touch and go. While they were ultimately able to secure Coleman’s appearance in the special, her schedule made it impossible for her to join Capaldi and company on set. As a result, the scene was shot in front of a greenscreen with each actor speaking to a tennis ball. But while this solution may have been less than ideal, in at least one sense it proved to be a blessing in disguise – it brought a particular significance to longtime producer Steven Moffat’s farewell:

“My last real moment of production wasn’t any of the ones anyone thinks it was. It was in the ‘Top Gear’ office at the old TV Centre – which is now the BBC Worldwide offices – with a skeleton crew, and Rachel and Jenna. That was my very final moment on ‘Doctor Who’. At the old TV Centre. As it should be.”

But all these scheduling hurdles also necessitated some changes to the cameo itself. As originally scripted, the scene would have seen the Doctor’s memories of Clara restored, just as in the finished special. But in addition to that, Clara would have also had a brief back and forth with the Doctor, Bill, and Nardole, which would have culminated in the following exchange:

Doctor: “I’ll tell you something, though. You were always my favourite.”

Clara: “Who was?”

Bill: “Which one?”

Nardole: “I know.”

After this, the Doctor would have returned to the TARDIS with a mischievous laugh before regenerating.

The first season of ‘Doctor Who’ following Moffat’s departure will air later this year, though the BBC has yet to announce a premiere date. Be sure to check back with ScienceFiction.com for more ‘Doctor Who’ coverage as the premiere approaches.