A role as daunting as Hamlet and one that gets slightly more attention on the internet, Doctor Who is a much sought-after part on television.

The BBC's long-running family sci-fi show has adoring and vocal fans around the world, so one must wonder why each actor who plays the Time Lord decides to move on. Why would they want to leave this actor's paradise?

Was it even their decision?

Here, Doctor by Doctor, we go through the murky and, in some cases, not so murky reasons why actors "quit" the TARDIS.

1. William Hartnell

BBC

Although Hartnell wanted to stay in the role that was beloved by millions and had helped create a massive hit for the BBC, ill health played a part in his leaving.

The actor, who was in his late fifties at the time, was increasingly erratic as his health declined, leading him to forget lines and require scenes to be re-shot. Producers took the dramatic, unprecedented (and not to mention, historic) step of replacing their lead actor.

If you want a dramatic recreation of this time, we do recommend you check out An Adventure In Space & Time from Sherlock co-creator Mark Gatiss.

2. Patrick Troughton

BBC

Pretty straightforward here.

Troughton, already a very familiar face/voice in the UK, took on the role on the proviso that this was a three-year gig. He also commented on the fact that, as an actor, he didn't want to be typecast.

3. Jon Pertwee

BBC

Publicly, Pertwee stated that the Doctor Who "team" was breaking up: Robert Delgado (The Master) had died and Katy Manning (companion Jo Grant) had left. However, in the same year (1974), Jon also spoke of back pain which had afflicted him for the past two seasons as a reason for quitting.

Elisabeth Sladen, who was effectively Manning's replacement as Sarah Jane Smith, revealed that Pertwee had asked for more money (not an unreasonable request) but the BBC didn't agree. Thus, he resigned from the role.

There's anecdotal support for this financial focus. For example, when asked by Terry Wogan if he was happy to be back in the role for the 1989 stage show 'The Ultimate Adventure', he replied: "Oh, sure, the money's good."

Pertwee's also on record as saying he didn't get a lot of money for Doctor Who, and Tom Baker often talks of teasing Pertwee about how much money he got paid for events.

4. Tom Baker

BBC

Towards the end of his tenure in the TARDIS, Baker was – he admitted – not an easy man to work with. He fought with directors, writers and, crucially, producers and is quite happy to 'fess up to his difficult nature.

On numerous occasions, Tom has said that he handed his "notice" in at the end of every year but was talked back into staying as the Doctor (the most popular to date at that time).

But when producer John Nathan-Turner came along, attitudes changed. JNT, as he is affectionally known, wanted to bring the show into the futuristic decade that was the '80s. Who got a shiny makeover.

A makeover that would see Baker's notice finally accepted.

5. Peter Davison

BBC

Perhaps one of the most clear-cut reasons, here. Davison took Troughton's advice of not staying longer than three years despite producer John Nathan-Turner asking for him to stay.

He did say, however: "It was very demanding, so I was too tired to feel sad when it was all finally over."

Over the years, Davison has expressed regret at not doing a fourth season in the TARDIS due to the rise in quality of scripts during his third and final season (with classics like his swan song, 'The Caves of Androzani').

He'd already handed his notice in by this time, so the decision was made.

6. Colin Baker

BBC

Although Colin once stated he wanted to beat Tom's record in the role, he ended up being the Doctor for the shortest time to date.

His time in the TARDIS was fraught: his second season, the aptly-named The Trial of a Time Lord, was delayed and fandom felt cancellation was nigh (causing Baker and various other luminaries to release the non-charting single 'Doctor In Distress').

Whilst the show wasn't canned, Colin was. His contract was not renewed although he was asked to come back for four episodes in the following season for his regeneration story. The actor, perhaps rightly, felt more than a little aggrieved and refused the BBC's plans: "I told them what they could do with their offer."

Colin told The Sun in 1987: "I have been treated shabbily."

7. Sylvester McCoy

BBC

Another candidate with a claim to having been poorly treated.

Doctor Who, as we know now, came to an end in 1989, but the show wasn't actually officially cancelled at any stage. McCoy has often lamented the short-sightedness of the BBC given that he and companion Ace (Sophie Aldred) were just hitting their stride. So this entry is an oddity: he didn't leave and he wasn't sacked (as such).

McCoy did make a glorious return for the 1996 TV movie where he handed the TARDIS keys over to Paul McGann.

8. Paul McGann

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Currently starring as another doctor in the BBC's long-running soap Holby City, the story of McGann and Who is a slightly sad one.

For one night only, back in 1996, the Withnail & I actor was most definitely the best thing about the ill-fated Doctor Who TV movie. But a series didn't follow, and fans had to make do with his Big Finish audio dramas.

When the show returned, some nine years later, McGann was nowhere to be seen. Not even a regeneration. But what happened?

Speaking at the BFI in the show's 50th anniversary year, the Eighth Doctor star told fans he would have come back to the role if the then-showrunner Russell T Davies had asked. The clean slate of 2005 resulted in McGann's removal from the role.

Whovians were rewarded with more McGann action during the 50th anniversary in the Steven Moffat-penned mini-episode 'The Night of the Doctor'.

9. Christopher Eccleston

BBC

We may never known precisely what happened here.

Doctor Who made a blistering return to television in 2005 with Eccleston as the Ninth Doctor and Billie Piper as his best bud Rose. But, Whovians around the world were rocked to their very core when it was announced that their new Doctor was leaving at the end of the season.

Whilst showrunner Russell T Davies stated that the plan was always to have the regeneration take place, recent comments by Christopher Eccleston have suggested that he himself quit the show.

He says the relationship with Russell and the producers (which included Julie Gardner, Mal Young and Phil Collinson) broke down "irreparably" at the start of filming and "never recovered".

Eccleston added: "They lost trust in me, and I lost faith and trust and belief in them."

10. David Tennant

BBC

Tennant rather spectacularly announced his decision to leave Doctor Who live on ITV during the National Television Awards in 2008.

Deciding to move on after making the role his own, the Scottish actor didn't want to "outstay" his welcome, saying: "It would be very easy to cling on to the TARDIS console forever and I fear that if I don't take a deep breath and make the decision to move on now, then I simply never will."

According to Russell T Davies, David did a have a "wobble" and seriously thought about staying on as the Time Lord. So much so that he met with Steven Moffat to discuss his plans though, in the end, stuck to his guns and hung up his sonic screwdriver.

11. Matt Smith

BBC

"When ya gotta go, ya gotta go!" Matt stated in his official leaving statement in 2013.

Later that year, The Crown star commented, "I'd have very happily done another year," adding, "for me, it just felt like the right time to move on".

Like Davison before him, Smith has publicly stated he regrets leaving the role so soon having wanted to do a full season with co-star Jenna Coleman (Clara). Steven Moffat has also stated that he originally planned to quit at the same time as Matt.

12. Peter Capaldi

@Markgatiss Twitter

In an emotional interview on BBC Radio 2, Peter Capaldi announced that he was leaving the show. The Twelfth Doctor said it was "the right time to move on".

Later that same year, Capaldi revealed his own self-doubt about playing the role for longer. He commented: "I want to always be giving it my best and I don't think if I stayed on I'd be able to do that. I can't think of another way to say, 'This could be the end of civilisation as we know it'."

The Thick of It actor also hinted that complacency may have been a factor too, adding: "I really never wanted to get to a place where I knew how to do this, because that's not what being creative is. The actual amount of time we were spending on the show, I realised I was getting the hang of it. And that made me frightened."

And in April 2018, he told Australia's Courier Mail that the "brand is a lot of work," adding: "There's a lot more than just acting."

Doctor Who airs on Sunday nights on BBC One.

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