For Whovians, traveling with the Doctor in Doctor Who seems like it would be a dream come true. Being one of the Doctor’s companions means exploring all of time and space, witnessing historical events, and seeing strange new worlds. However, it can also be incredibly dangerous, and like many of the Doctor’s former companions, it can change you for life.
The newest Doctor-lite episode of Doctor Who, “Lucky Day,” proves this fact more than ever. Although the Doctor’s current companion is Belinda Chandra (Varada Sethu), the episode puts the spotlight on Ruby Sunday (Millie Gibson) from the season 14 cast of Doctor Who. Although she was only with the Doctor for a short while, like all companions, Ruby found herself taking on some of the Time Lord’s mannerisms.
Most Companions Become Like The Doctor After Traveling With Him
Even Ruby Catches Herself Acting Like The Doctor
In “Lucky Day,” Ruby is faced with the seeming return of a group of aliens called shreeks – terrifying beasts which mark their prey and return a year later to hunt them down. This time, she has to face the threat on her own, without the Doctor. Luckily, Ruby has dealt with these aliens before, and though he’s not with her, she steels herself and confronts the danger just like the Doctor would.

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Although she is terrified, Ruby knows that she is the only one who can protect the people around her, As she looks for the shreek, Ruby starts to talk to herself, saying “Okay, just me this time. Talking to myself, that’s very Doctor.” The fact that Ruby recognizes that she’s developed some of the Doctor’s habits means that she’s very aware of what’s happening to her – unlike many of the other companions who have traveled with him before. Like most companions, the influence the Doctor left behind has become a part of who Ruby is – for better or for worse.
Ruby Isn’t The First Doctor Who Companion To Morph Into The Doctor
Companions Like Donna & Sarah Jane Went Through The Same Thing
Ruby isn’t the only one who was forever changed by the Doctor in Doctor Who. Who wouldn’t be, after the things they’d done and seen? In some cases, companions becoming more like the Doctor is quite literal. For instance, Donna Noble became the Doctor-Donna in Doctor Who season 4, when the DNA of the Doctor’s severed hand fused with hers to create a human-Time Lord hybrid. Unfortunately, the change was too much for her brain to handle, and the Doctor was forced to wipe Donna’s memories – a tragedy for the woman who was possibly the Tenth Doctor’s best companion.

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Even companions from classic Doctor Who episodes returned to the new series as very different people. In season 2 of the new series, the Doctor reunites with Sarah Jane Smith, who had previously been the Fourth Doctor’s companion. Decades after she had traveled with him, Sarah Jane started investigating paranormal events on her own. She even formed her own group known as the Bannerman Road Gang, who helped to defend the earth from outside threats in the Doctor Who spinoff, The Sarah Jane Adventures. We also can’t forget Mel and Ace, companions of the 7th Doctor who later joined UNIT.
Making Companions Become Like Him Is One Of The Doctor’s Most Dangerous Traits
Though It Might Not Be His Fault, The Doctor Still Feels Guilty For His Influence
A life traveling with the Doctor is filled with adventure, but also many dangers. Daleks, Cybermen, Weeping Angels, and Soltarans are just some of the most iconic villains that the Doctor and his friends have faced. Yet perhaps the most dangerous aspect of being one of the Doctor’s companions is the fact that they often become just like him.
On more than one occasion, the Doctor has gotten his friends killed thanks to his actions.
At first glance, this might not seem like a bad thing. After all, the Doctor is kind, brave, and heroic – but he is also reckless, often charging into dangerous situations without thinking. On more than one occasion, the Doctor has gotten his friends killed thanks to his actions. That isn’t to say that it’s all the Doctor’s fault, yet the guilt continues to weigh him down after 15 thousand years.

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Despite his efforts, even the best Doctor Who companions eventually end up like the Doctor – whether it’s because they want to impress him, or naturally evolve to be more like him. While not all bad, the changes that the Doctor’s companions go through as a result of traveling with him are the most dangerous reality that they face.

- Release Date
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December 25, 2023
- Directors
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Douglas Camfield, David Maloney, Christopher Barry, Michael E. Briant, Barry Letts, Michael Ferguson, Richard Martin, Peter Moffatt, Pennant Roberts, Lennie Mayne, Chris Clough, Ron Jones, Paddy Russell, Paul Bernard, Michael Hayes, Timothy Combe, Morris Barry, Gerald Blake, Graeme Harper, Waris Hussein, Rodney Bennett, Mervyn Pinfield, Hugh David, John Gorrie
- Writers
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Russell T. Davies, Dave Gibbons, Kate Herron, Steven Moffat
- Franchise(s)
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Doctor Who / Whoniverse