What's happening to Ruby Sunday in Doctor Who? All the theories

The first episodes of season 14 of Doctor Who have properly introduced us to our incredible TARDIS duo, Ncuti Gatwa's Fifteenth Doctor and Millie Gibson's Ruby – but almost immediately, it's clear something's off with Ruby.

She makes it snow multiple times indoors, the Doctor's memory of the church on Ruby Road changes completely, prompting him to run a DNA test on her, and Jinkx Monsoon's Maestro appears haunted by her. Plus, the mystery with her mother is only deepening after a hint from the Ambulance (played by Susan Twist) in Steven Moffat's new episode Boom.

So, is the mystery going to continue in Steven Moffat's upcoming episode Boom? And what exactly is going on with Ruby?

What's happening to Ruby Sunday in Doctor Who?

First of all, let's assess all the strange goings on in those those first three episodes.

Space Babies

When talking about how Ruby was left at the church on Ruby Road, the Doctor is transported back to the scene – and his memory changes.

He sees the mysterious hooded figure in the snow (who we're all assuming is Ruby's mother at this point) pointing at him – before returning to the present and finding it’s actually snowing around them. In the original memory, the figure never pointed at him.

Concerned, the Doctor tells Ruby: "I have been to the ends of time and back and I have never seen anything like this before.”

While he reassures her, he looks worried and secretly runs a DNA test on her, scanning for age, species and genetic identity. Just in case, we zoomed in on those results – her genetic ID came back with the characters JD6784, species came back as homo sapien and age came back as 19. All seemingly normal so far – except for her making it snow once again.

Plus, why exactly did the Doctor run the test? What was he hoping to find?

The Devil's Chord

So, when it comes to the battle in The Devil's Chord, Maestro hoists Ruby into the air – but Ruby seems to fight back. The Carol of the Bells, the tune that was playing on the day Ruby was born, begins to play and it begins to snow again.

Maestro is disturbed and references an unknown power that may have been present on the day of Ruby's birth, saying: "How could a song have so much power? And power like him? The oldest one, from the night of her birth. He can’t have been there. What for?"

Could it have something to do with The One Who Waits?

Before Maestro is defeated, they say of Ruby: "This creature is very wrong."

Boom

The mystery is far from over in Steven Moffat's Boom, which sees Ruby on the brink of death after being shot by Anglican Marine Canterbury.

The Ambulance identifies her calendar age, before attempting to identify her biological next of kin - but it begins to glitch, suggesting this is something it hasn't encountered before.

Weeping, Ruby asks who her next of kin is, and it once again begins to snow. Canterbury says: "That's not possible. It doesn't snow here. It never snows."

The Doctor suggests the snow is a sign of hope - before it stops as Ruby's vital signs begin to fail. Thankfully, Ruby recovered by the end of the episode but the mystery of what's happening to her is still ongoing.

While Davies hasn't given us answers just yet, he has confirmed they're coming this season. He told CinemaBlend: "I mean, there is a meaning, there is a significance, it will be explained.

"It's not going to be one of those annoying mysteries that at the end of the season, we go, ‘Ahh, keep watching. We will continue this mystery.’ There's a definite answer. It is meant to be a mystery."

He also revealed how he thought up the idea of the snow, adding to the outlet: "I can actually remember the moment I thought of it. I wanted the memories of Ruby's birth to keep breaking through as a child. She's abandoned as a foundling on a church doorstep in the snow at midnight."

Of course, we have no idea what exactly is going on just yet, but we do have some theories – and we're assuming it comes down to Ruby's birth mother, whose identity is still unknown.

Could Ruby's mother be trying to contact her somehow, by means of making it snow, sending her the tune of The Carol of the Bells, and changing the Doctor's memory?

Showrunner Russell T Davies has expressed how important Ruby's back story will be this season, so it's a strong possibility that her mother could be behind these strange happenings.

Another possibility is that someone – or something – is meddling with the Doctor's memories. It wouldn't be the first time a foe has found its way into the Doctor's mind, and Davies has stressed just how powerful the villains are this season, with Maestro being described as "the Doctor's most powerful enemy yet".

Or, could it just be Ruby herself? Could something sinister be happening to her, or could this be a power that she could use to her advantage?

Whatever it was, it certainly seemed to help her in fighting back against Maestro.

Doctor Who will continue on 18th May on BBC iPlayer and BBC One.

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