From reptile-like creatures to metallic men to those without a physical form, a variety of villains and monsters of all shapes and sizes have graced our tellies during the 50 year run of 'Doctor Who'.
Some of the designs and characteristics have been so effective that both children and adults find the nearest sofa to hide behind.
However, some monsters are less than convincing thanks to questionable costumes, dodgy make-up whilst one particularly ridiculous monster simply looked like a giant Bertie Bassett - yes, I'm talking about you Kandyman!
In reverse order here are the 10 scariest creations in the 'Doctor Who' universe:
10. The Eternals
They are beings that live for eternity, manipulate objects and read minds. They rely on mortal beings, who they dismissively dub "ephemerals", to keep them entertained.
In the 1983 adventure 'Enlightenment' they pluck a number of ephemerals from their time to sail historic vessels across space in a deadly race with little care for their lives.
When I watched this story for the first time, The Eternals' chilling nature and deadly serious nature left me quite unnerved.
As a bonus, because they looked human the production team didn't have to splash out on creating a new costume.
9. Ice Warriors
You couldn't have a list of monsters without including something from Mars, could you?
The Ice Warriors made their debut in 1967 attempting to take over the Earth and they returned in the 2013 episode 'Cold War' as Grand Marshall Skaldak controversially left his armour and ran amok on a Soviet submarine before being rescued by his own kind.
What frightened me was their speed, crocodile-like skin and whispery voice. However, as colonising Mars is a long way off, humanity probably won't encounter something like the Ice Warriors in my lifetime. Phew!
The original inhabitants of Earth, the Silurians are a race of scientifically-advanced Homo reptilia that went into hibernation.
They were introduced in the 1970 story 'Doctor Who and the Silurians' before their aquatic cousins the Sea Devils were introduced in 1972.
The Silurians returned with an updated look in 2010 as a tribe were awoken by underground drilling in a Welsh village. Sadly they didn't have strong Welsh accents - reptiles with a Welsh drawl would be quite the sight!
They aren't the most menacing of aliens nor are they the most threatening but the prospect of an advanced race emerging from hibernation - potentially with a broad Welsh twang - to reclaim the planet is quite worrying.
7. The Master
The Master is an evil Time Lord who's determined to defeat the Doctor and control the universe - with that name he is also quite egotistical.
He first showed up in the 'Terror of the Autons' and went through a number of appearances and bodies before disguising the fact he was a Time Lord.
The Master became Prime Minister of the United Kingdom and took over the Earth before being shot by his wife.
At least Time Lords also get hassle from the women in their life just like us.
He is the antithesis of the Doctor but his elaborate ploys can make him seem slightly over the top as a villain. Perhaps he's a character to file under the heading 'Pantomime'.
A clone warrior race from the planet Sontar, they thrive in battle and are fearless of death. They are stocky creatures with just three digits on each hand and they look quite like giant baked potatoes.
If potatoes could talk then you'd have your own mini Sontaran - at least if it tried to kill you then you could just stick it in the oven for 50 minutes at gas mark six and you'd have a nice meal.
However they weren't that easy to deal with when they first appeared in the Jon Pertwee serial 'The Time Warrior' and they were slightly re-designed for their return to the show in 2008. Somehow they looked even more like potatoes.
They may look like the nation's favourite root vegetable but I think their warrior nature makes them quite a formidable race.
5. The Cybermen
Originally from the Earth's twin planet Mondas, the Cybermen are humans who decided, hopefully not on a whim, to add mechanic parts to their bodies to ensure their survival whilst deleting every emotion.
If they thought it was sensible to turn themselves into metal monsters then it probably was a wise move to remove their emotions...
They first appeared in the 1966 serial 'The Tenth Planet' and they gradually upgraded with each story - appearing at their most advanced in the 2013 episode 'Nightmare in Silver'.
I find the idea that humans resorted to such drastic measures to survive is where the true horror lies.
However, for a supposedly powerful enemy, they are always quite easily defeated.
If shop dummies coming to life and attacking people isn't a scary thought then I don't know what is. They are animated by the Nestene Consciousness and have weapons concealed within their hands.
Thanks to the Autons I have taken to online shopping instead of going to my local high street.
They first appeared in the Third Doctor's debut story 'Spearhead from Space' and they have shown up twice in the new series - the Ninth Doctor's opening story 'Rose' and as Roman soldiers in 'The Pandorica Opens'/ 'The Big Bang'.
Their concept is perhaps more frightening than the end product but who doesn't look twice when walking past a shop dummy?
3. The Silence
"Silence will fall" was heard repeatedly throughout Series 5 but it was only in the opening episodes of the next series did we actually see what the Silence were.
They are forgettable monsters - quite literally. When you look away from a Silent (their singular name) then all memory of it is forgotten but the Doctor manages to defeat them thanks, in part, to the historic 1969 moon landing.
They form a major part of a religious movement of the same name who are out to kill the Doctor to stop him from answering the oldest question in the universe.
'How did One Direction become so popular?'
Sorry, wrong question. 'Doctor who?'
They haven't been seen since the end of Series 6, except they might have but we just can't remember…
The Silence are such a captivating creation and they are easily one of the most psychologically frightening 'Doctor Who' monsters.
2. The Weeping Angels
The Weeping Angels are a quantum-locked alien species - they turn to stone when they are looked at but move quickly and silently when they are not seen. They cover their eyes to avoid seeing each other as they would be trapped in stone form.
It must be a lonely life.
They are actually pretty nice monsters as they 'kill' by sending victims back in time but they began snapping necks in the two-parter 'The Time of Angels'/ 'Flesh and Stone'.
I wept as a lone Angel sent the Doctor's companions Amy and Rory back in time in 'The Angels Take Manhatten'.
I should also let you know that I carefully walk past any statue I see - for all I know it could easily be an angel and I don't fancy being zapped back to the 1900s.
1. The Daleks
Hailing from Skaro and created by the evil Kaled scientist Davros, they first appeared in the show's second story, 'The Daleks', and every Doctor - bar the Eighth - has faced them on-screen.
They are a genetically mutated race stripped of compassion placed within a mechanic exterior. Whilst they may look like pepper pots with plungers and whisks they are out to conquer the universe.
Their origins are shown in the 1975 serial 'Genesis of the Daleks' whilst they managed to go up a flight of stairs for the first time in the 1988 serial 'Remembrance of the Daleks'.
They most recently appeared in 'Asylum of the Daleks' when they sent the Doctor, Amy and Rory to destroy the Asylum - the home of insane Daleks.
The Daleks may not be as scary when they first appeared but the fact they would kill you instantly, no matter what, with their whisk-like weapon is chilling.
What do you think is the scariest monster featured in 'Doctor Who'?
Alex Harris wishes to travel in time and space with the 11th Doctor.
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