Call the Midwife's Nancy poses a problem for fans of the show

Now, that would be frustrating enough even without all of the uncertainty surrounding her future. The period drama is an ensemble that suffers when any of the core cast are missing for any length of time.

And yet, actor Megan Cusack has confirmed that "she's not leaving us just yet", suggesting that there could be heartbreak on the horizon for the midwife.

But while that would be incredibly sad for Nancy, viewers might not feel the same way, which puts the audience in an uncomfortable position. Allow me to explain...

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While Cusack's character was excited about being offered the job at Netherditch hospital, in part due to the house that comes with it, it was her engagement to pharmaceutical salesman Roger Noble that ultimately persuaded her to accept.

"It's right in the middle of my sales patch," he said when she first told him. "You have to take it, Nancy. You'll be nearer to me, until we get married."

So, perhaps her disappearing act isn't that at all, but she's simply taken up her new post without any fanfare and will return to east London in the spring to tie the knot.

But if Cusack really isn't leaving Call the Midwife, surely it's all but confirmed that she will return to Nonnatus House for good? And that could signal a bump in her relationship with Roger.

It would make little sense for Nancy to uproot her daughter Collette from London and lay down roots elsewhere, only to return weeks later – unless, of course, her new relationship breaks down and she needs the love and support of her Poplar family to help her get back on her feet.

She was initially wary about going on a date with Roger for fear of how it would impact her child, so why would she return if not forced to?

But as devastating as that would be for Nancy, who has already endured significant hardship in her life, fans of the show don't want her to leave.

Not only have they enjoyed watching her grow into the woman she is today, much of which is tied to her very sweet relationship with Collette, her dry wit and spirited nature offsets the show's more sentimental moments and prevents the writing from tipping into full-blown mawkishness.

So, as much as the fandom are right behind Nancy's happiness, there will be a large portion of people who would have her endure some misfortune if it meant Cusack was staying put – and that's just not very nice, is it? And certainly not in the spirit of the show.

Of course, the actor might have been bluffing to preserve our surprise, with Nancy indeed set to leave.

It could well emerge at the end of season 14 that she is on her way, and having just welcomed Sister Catherine into the fold, it's not like they'd be short on numbers.

Regardless of what happens with her Roger, she might decide that Netherditch hospital is a better fit. And as content as she and Collette were at Nonnatus House, there's no reason why they couldn't have that sense of community in another part of the country.

But that outcome feels unlikely.

Perhaps Roger's sales patch will move to east London and Nancy will be spared heartbreak after all, the best of both worlds.

But that theory also feels tenuous.

It was a similar situation with Trixie last season when she followed her husband Matthew to New York. His financial troubles had upended their lives and he felt that the only way for him to rebuild was to explore a business opportunity with an old friend overseas.

But while viewers supported Trixie packing her bags – she was utterly miserable without him, and the audience had invested time and emotion in their relationship over the seasons – they didn't want the midwife's exit to be permanent.

Thankfully, writer Heidi Thomas figured out a way to bring her back while also keeping Trixie and Matthew's marriage in tact – although it should be noted that viewers enjoyed watching them interact together on-screen rather than being fed the occasional update.

It also remains to be seen what will happen to Trixie if Olly Rix does not return.

If Matthew decides to stay in the States, will that bring about the end of their marriage? It would be incredibly painful for Trixie to suffer yet more loss. But again, fans of the show would likely accept such a development if it allowed Helen George to remain on our screens.

And the same also goes for Nancy.

As much as viewers support her happiness, there's no world in which they want to wave goodbye.

Call the Midwife airs on Sundays at 8pm on BBC One and BBC iPlayer.

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