The sci-fi TV show Torchwood may have originally started out as a spin-off to Doctor Who, but it quickly learned to stand on its two feet. Even though it hasn't aired a new episode in almost a decade - even though it's never been officially canceled - the show continues to captivate viewers.

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One of the main reasons why fans continue to watch Torchwood is the rich number of characters that occupy the fictional world. Some of them are heroes, others are villains. Some turn out to be more sympathetic, others not so much. But all of them are different, which also means they would end up in different Hogwarts houses.

Esther Drummond: Gryffindor

Esther Drummond

The fourth and final season of Torchwood saw the introduction of several important new characters. One of them was Esther Drummond, who starts helping Jack and Gwen, the two surviving members of Torchwood Three.

However, she dies in the season's finale. Esther has a sweet and caring personality. At the same time, she's smart and has considerable technical knowledge. Nevertheless, her main strength lies in bringing people together, which is why she would fit well in Gryffindor - since teams seem to thrive in this Hogwarts house.

Rhys Williams: Hufflepuff

Torchwood Rhys Williams

Rhys Williams is Gwen's boyfriend and later husband. Their relationship faces challenges once Gwen starts working for Torchwood and gets closer to Jack. She even cheats on Rhys with Owen. But the couple manages to overcome their differences and remain together.

Rhys's life might not be as dangerously glamorous as Gwen's, but he stands by her side, supports her and remains loyal to her. That's one of the reasons why she chooses him in the end and has a daughter with him - because he's there for her, unlike Jack who runs away when the Doctor visits Cardiff.

Martha Jones: Ravenclaw

Martha Jones in Torchwood

Martha Jones played a much more prominent part in Doctor Who, as she was the Tenth Doctor's companion in the third season. But she also visits Torchwood and stays for a while, helping the team. Martha is young but has considerable medical knowledge, and her expertise comes in handy. Plus, she's strong and resilient, pursuing her goal until she reaches it.

Her ambition and intelligence place her in Ravenclaw. What's more, she was one of the few companions who left the Doctor on their own terms, not because something bad happened that forced them to leave.

Andy Davidson: Hufflepuff

Torchwood Andy Davidson

Andy Davidson isn't one of the main characters, but he appears in Torchwood on more than one occasion. He and Gwen worked together when Gwen was still working for the police, and they seemed to be friends. They remain fairly close even after Gwen switches her job and joins Torchwood instead.

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Andy seems like a good guy, and he tries to help Gwen whenever he can even though other people in his place could feel betrayed. After all, once Gwen joins Torchwood, she doesn't spend as much time with her old friends as she once did. But Andy still remains her loyal friend.

Ianto Jones: Hufflepuff

Ianto Jones

Ianto Jones initially doesn't have a big role in Torchwood. He mostly guards the door into the secret institute and makes excellent coffee. But he becomes more active as time progresses.

Ianto's smart and kind, but his most obvious character trait is his loyalty. That puts him in Hufflepuff. Ianto first tries to save his girlfriend Lisa who's been turned into a Cyberwoman, even though the odds are stacked against him. He then grows closer to Jack and switches his loyalty to him, and that remains the case until Ianto's death in the third season.

Suzie Costello: Slytherin

Torchwood Suzie Costello

Before Gwen joins Torchwood Three, it's Suzie Costello who's Jack's second-in-command. Suzie is ambitious and wickedly smart. But she also turns out to be dangerous.

She takes a dangerous alien instrument out of Torchwood and when Jack confronts her about it - and the murders she caused - she tries to kill him. And she would have succeeded if Jack hadn't been immortal. Suzie's charming on the surface, but has a darker side to her, which is typical for some Slytherins.

Toshiko Sato: Ravenclaw

Toshiko Sato

Toshiko Sato, better known simply as Tosh, is by far one of the smartest people on the team. She's this Torchwood's main scientist and her expertise often helps the team to solve problems they wouldn't be able to deal with otherwise.

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Tosh can be quite awkward when it comes to dealing with others in a more relaxed way. She's also not that good at romantic relationships and mostly focuses on her work like hard-working Ravenclaws sometimes do.

Owen Harper: Ravenclaw

Owen Harper

Similar to Toshiko, Owen's ideal house would also be Ravenclaw. Owen seems careless at times, but he's highly intelligent and well-educated in his chosen area of work (that is medicine).

He also has a tendency to push people away sometimes. That's one of the reasons why he and Toshiko never make it work even though she's in love with him and Owen also cares for her in his own strange way.

Gwen Cooper: Gryffindor

Torchwood Gwen Cooper

Gwen Cooper eventually becomes Jack's right hand and one of his closest friends. She's warmer than her boss, thanks to the fact she's very young in comparison to him. Gwen is a kind-hearted person who's willing to fight for her friends - and the entire planet - no matter the danger she faces.

She even was able to go through her whole wedding while there was an alien baby growing inside her - a highly dangerous one. If that's not bravery, it's difficult to say what is.

Jack Harkness: Slytherin

Torchwood Jack Harkness

Captain Jack Harkness could potentially belong to Gryffindor as well, thanks to his brave nature. But by the time the audience meets in Torchwood, he has already lived a long time, far longer than most people. That leaves him more cynical and jaded than his colleagues. Jack also realizes that sometimes to succeed, people have to sacrifice something dear to them.

His sometimes grim but overall realistic view of the world and his similarly grim determination combined with intelligence place him in Slytherin. And then there's the matter of his personal charm that even Tom Riddle himself could draw inspiration from.

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