After a rough start, Torchwood became a valuable program in its own right. It focused on the Doctor's old companion, Captain Jack Harkness as he took over the running of the Torchwood Institute after it fell during the Battle of Canary Wharf. Jack then put a team together to fight off alien threats.

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Unlike Doctor Who, or its sister show, The Sarah Jane Adventures, Torchwood struggled a bit during its first season. It seemed to lack identity and went out of its way to prove that it was an adult series. Though there were some amazing episodes, there were also those that simply didn't hit the mark.

A Day In The Death (Season 2, Episode 8)

Generally speaking, Torchwood's second season was a lot better in terms of quality and character development. The characters themselves seemed closer and they weren't all at each other's throats the whole time. They also learned to trust their leader a lot more, and in return, Jack confided in them.

However, there were some episodes that had so much potential but failed to deliver. In particular, the episode arc surrounding the return of Martha Jones. Martha appeared in Torchwood for three episodes but only the first was (marginally) focused on her. It was a waste of such a good character.

End Of The Road (Season 4, Episode 8)

Miracle Day was an uneven season, to say the least. Only Jack and Gwen Cooper remained from the original cast and the show moved oversees to America. There were some excellent episodes within the season, and the performances from everyone involved were sublime but the season felt too long.

The miracle in question was that everyone on Earth had lost the ability to die and while this made for an intriguing premise, it did start to become a bit dull eight episodes in. Many episodes within Season 4 just felt like filler episodes and "End Of The Road" was no exception.

Countrycide (Season 1, Episode 6)

The cast of Torchwood series 1 posing for a promotional photo

In all fairness, we have to admit that even during its earlier seasons, Torchwood wasn't afraid of trying something new. This particular episode saw the team on a group outing to the Brecon Beacons in South Wales, after discovering that people had been going missing and never seen again.

It transpired that aliens were not in fact responsible for these disappearances. Instead, the inhabitants of a small, nearby village were actually cannibals and were kidnapping outsiders and then feasting on their remains. It was a solid story but the pacing was off and the ending felt a bit too rushed.

Ghost Machine (Season 1, Episode 3)

This story wasn't bad per say, it just wasn't brilliant. In fact, it was simply unremarkable. The plot revolved around the Torchwood team tracking down an alien artifact which allowed the user to literally revisit past events that had happened in whatever location they were at.

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The lack of a solid alien threat here didn't particularly help to advance the plot and although it was nice that characters other than Jack and Gwen got a look in, Ianto and Tosh were still noticeably underused. The story itself was rather underwhelming and it didn't contribute anything to the overall season.

Dead Of Night (Season 4, Episode 3)

John Barrowman as Captain Jack in Torchwood

As previously mentioned, the fourth season of Torchwood suffered from being dragged out for too long. As such, many episodes felt like they were merely there to fill the void. Indeed, the season could have probably been reduced down to five episodes, like with Children Of Earth.

"Dead Of Night" was one such filler episode that featured the Torchwood team on the run (yet again). By this point, the thrill of humanity's sudden immortality was starting to wear off slightly and fans were keen to see the plot advance. Unfortunately, this didn't happen, other than the reveal of a few tidbits of information.

Meat (Season 2, Episode 4)

Gwen and Rhys

This is the episode that introduced the world of Torchwood to Gwen's fiancé, Rhys Williams. Rhys's reaction was well written and superbly acted and so that in itself deserves praise. However, the rest of the episode felt as though it was lacking somewhat, despite an adorable scene between Tosh and Owen.

This was largely in part due to the poor quality of the episode's villains. Two brothers found a large alien refugee and began cutting it up and selling it to the public, without bothering to properly sedate the creature. They were pathetic and Torchwood should have been able to take them out easily.

Out Of Time (Season 1, Episode 10)

This was a more emotional episode of Torchwood, which is good as TV shows need to try out new formats to remain fresh. However, the episode itself fell flat. In "Out Of Time", the Torchwood team pick up three travelers who went through the rift from the past and ended up in the present, with no way back.

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The three characters were likable enough we guess, but as the viewers only had 50 minutes to get to know them, their eventual departures at the end of the episode felt rather pointless. It didn't really add anything to the rest of the season and the episode also had some pacing issues.

Captain Jack Harkness (Season 1, Episode 12)

Cast of Torchwood Starring John Barrowman

In this episode, Jack and Toshiko got sent back in time by the rift to right in the middle of World War Two. They had no way to get back and so they had to rely on Gwen, Owen and Ianto to rescue them before they died in the past. Additionally, the real Captain Jack Harkness was also present, which posed a problem.

According to Jack, he stole his name from a deceased Captain, thinking it didn't matter. However, over the course of the episode, we find the two men become attracted to one another. In the present though, the animosity between the Torchwood team went past boring and into dangerously violent.

Combat (Season 1, Episode 11)

Owen Harper

Owen Harper was a completely unlikeable character for the whole of the first season of Torchwood. We get that Torchwood is a grown-up show and so not all the main characters should be immediately loveable but there was absolutely nothing at all redeemable about the show's resident doctor.

"Combat" was an Owen-centric episode, and probably suffered the most because of it. It centered around an illegal, underground fight club featuring depressed and angry men against a Weevil, a vicious alien. Of course, Owen himself ended up in the cage because he was feeling sad and upset and we didn't care less.

Immortal Sins (Season 4, Episode 7)

John Barrowman in Torchwood

Miracle Day was slow enough as it was, so why on Earth was this episode even featured? This was a predominantly Jack-centric episode, which usually makes for good viewing. However, instead, this episode gave fans an hour of watching Jack have lots and lots of sex with a cute man who then betrays him.

It didn't really go anywhere, and the colored tint on all the flashback scenes was irritating to watch. What's worse is that this episode portrayed the villains of the season for the first time, only to reveal that they were just a bunch of men. The only redeeming part of this episode were the interactions between Gwen and Jack in the present day.

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