Anatomy Of A Special Effect


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Everybody loves a good special effect, or, perhaps more accurately, nobody really notices a good special effect. The preferred result is to leave people genuinely believing a man can fly or that a small boy is shooting electricity at a grotesque spindly nightmare monster.

We can talk about that second one because, well… we did it, we put that in a film. And forgive the self-praise, but we think it looked damn good, especially given the time constraints placed on its production (more on which down below).

Given that success, we thought we’d spread the goodwill and share everything we’ve learnt about producing that effect and others – about how to make (and then murder) a monster…

Now, before you read on, check out the effect here in our film Leadtime, specifically the sequence from 2 minutes 39 seconds in:

Fun, right?

So, key bit of context before we begin: Leadtime was produced as part of a 48-Hour Film Challenge. For those not in the know, that’s a competition where various teams of foolhardy filmmakers have to produce a short film from scratch over a weekend – writing, shooting, editing and yes, monster-making, all in an extremely tight, sleep-free 48 hour period.

Now, with that out of the way, let’s get started.

A special effect breaks down into three distinct parts:

  • The musculature: costume forms the real-world foundation of an effect. Even CGI-heavy creations often need some form of token costume to give the actors and post-production artists something to work with.
  • The bones: Your actors create the structure and underlying nature of the special effect. Good acting can be ruined by a special effect, but bad acting can rarely be saved by one.
  • The skin: Digital effects in post-production build on everything to create the finished product the audience sees. Do this badly and your viewers will be quick to notice exposed musculature and bone underneath.

So, how did we go about implementing each of those elements in Leadtime? Read on to find out.

The Musculature
We had two fantastic, endlessly inventive costume designers working on Leadtime – Morag Hickman and Magda Durka.

The Monster Makers Focused And Intent!!

Morag (top) and Magda (bottom)

Inspired by films like Pan’s Labyrinth, they set about conceptualising the monster, coming up with a design for a sinewy, insectile, carapaced entity that would almost glow in the dark.

The basis of that costume was a flesh-coloured, matte-lycra bodysuit with a lizard-like print, a smart choice for a couple of reasons:

  1. The script demanded an elaborate fight scene. Therefore, flexibility was a must.
  2. A bodysuit works as great base layer for further attachments and augmentations. And, given our designers planned for the costume to be truly terrifying and otherworldly, those would be an essential next step…
Monster in the Cinema

No Cinema goers were terrorised in the making of this movie (or not too many, at least…)

As Magda says “While working on the costume concept, I noticed that Morag had a bag of unusual materials with her. We dug into that and realised immediately that thermoplastic would be our friend. This heat-mouldable, waxy polymer offered a perfect solution for claws. Alien creatures should have claws!”

Thermoplastic is Morag’s go-to material for creating structural elements on the fly. It’s sculptable after submersion in hot water, it’s springy enough not to be a genuine danger to anyone, and it’s tough enough to stand up to rough treatment.

As the monster needed to be a clear threat, it was armed with six scything claws, a weird pointy mandible, and spines on the head, elbows, and anywhere else that felt like a good idea. Most of this was accomplished with thermoplastic pierced through the bodystocking or attached with double-sided sticky tape.

Mandible Adjustment, Morag Hickman is this season's mandible adjuster du jour

“Would you mind terribly if I adjusted your mandible?” “Please, go ahead”

However, while this hideous humanoid alien hedgehog was coming together nicely, it still looked a bit blank and didn’t have much secondary movement to show up in our super slo-mo camera takes. Therefore, the designers hooked some rusty-looking bundles of long, fake hair through the stocking and around the creature’s multiple spines, producing a disturbing ‘hairy insect’ effect along with a great flowing motion.

Just a few finishing touches remained. One, mixing fistfuls of black and red acrylic paints with hair gel, and plastering the hair up into a stiff, animalistic mane. Two, strategically applying paint to dirty up the monster even more, giving its skin a nasty sweaty sheen. And three, encrusting the claws with a good layer of blood and gore, a remnant of its encounters with previous victims…

All of this design work meant the creature looked brilliant on camera. The pale theme made it stand out starkly against the dark sets, especially when light glowed through the thermoplastic weapons, and the silhouette of the monster allowed for some wonderfully creepy, shadow-based cinematography.

Throwin' Shapes

The Bones
With a creature-feature like Leadtime, the actor playing the monster would usually have a long prep period to explore movement ideas with the director. However, in a 48-Hour Film situation, you only have a fraction of that: everything has to happen far, far faster it normally would.

Luckily for us though, we had an incredible actor on board, someone who could deal with those constraints magnificently: Jinny Lofthouse. Among other things, Jinny has an extensive background in fight choreography, meaning she has a mastery over physical, movement-based acting.

Jinny getting into character

Given that experience, Jinny was quickly able to find an approach to embodying the monster, much of it emerging organically from Magda and Morag’s creature design. The prosthetic extensions for the fingers lent themselves to spindly motions; the clacking, clutching claws created an unsettling sound when dragged across the surface of a dry concrete wall; and the way the costume restricted Jinny’s vision meant that only slow, careful movements were possible. Given the latter, the monster became a creature that crept around cat-like, stalking its prey from the shadows until, finally, the moment came to pounce.

Of course, this costume carried a a number of practical challenges with it as well…

“As a physical actor, it’s always a great pleasure to bring an inhuman character to life.”
says Jinny. “However it can come with its issues. For this project that would be the restrictiveness of the costume – I had to be sewn into it and so was unable to go to the bathroom. Then, since I couldn’t really see, moving around the location was genuinely problematic, especially when faced with stairs.”

So there’s an important lesson: when building a special effect, take good care of your actors. By transforming them into a monster from another dimension, you may have made them a lot less able to traverse our own…

Taking The Monster for a walk

The Skin
Ordinarily, it takes time, effort and careful planning to create good visual effect. On a film challenge you have effort and, if you’re lucky, a lot of coffee, so things have to be sped up and compromises made.  It’s an exercise in not only raw skill but problem-solving as well.

Outside of film challenges, digital effects sorcerer Cat Harris does this work professionally, generally using a piece of software called Houdini to produce complex effects for blockbuster movies. However, that’s a slow process. You need to build models and simulation setups in the 3D world, then output the 2D images from that, then composite them into the original footage. When really pressed for time, the best option is instead just to bash stuff out in 2D in Adobe After Effects.

Cat's overnight wear - crucial for a 48 hour filmshoot.

Cat’s overnight wear – crucial for a 48 hour film-shoot

Sometimes a spanner is found to have been carefully placed in the works without anyone realising that it is in fact a spanner and that its location is in fact the works. With Leadtime, when Cat received the footage to work on, she discovered that a key element of the monster’s screen presence was its tendency to flail around everywhere. In her own words, ‘this was not ideal’.

To explain: during the electricity attack effect, each of the lighting bolts needed to lock onto the monster’s body in a particular place and then stay attached to that location throughout the shot. You don’t want something hitting an ear in one frame and an armpit the next, as that would break the reality of the moment.

David Hing checks an actor for signs of life.

Now do that scene right or I’ll hit you again.

With smooth movement in the footage, you can mark a point on one frame and then another few frames later, the software working out the motion between them. However, in the case of Leadtime and the frantic flailing of its monster, Cat could only achieve the needed consistency by animating the lighting manually. Frame by painful frame.

As Cat says, “This is sloooow work”. Thankfully though, it’s also “infinitely improved by a room full of hilarious and talented – albeit slightly knackered, stressed and unwashed – people.”

So, just as you need to look after your intentionally blinded actors, make sure to give the same consideration to your overworked VFX artists…

The Finished Effect
When the crew saw the finished effect for the first time, they were speechless. Despite being produced in a hurry, it looked great, the talents and efforts of three different departments combined to make a genuinely terrifying, heart-pounding sequence.

You can have excellent acting and it will show.

You can have outstanding costumes and it will show.

You can have the flashiest CGI you’ve ever seen and people will leave thinking that, well, at least the effects looked cool.

If you have all three though, all working together in tandem, all with a shared vision of story and cinema, that’s when an audience is going to be truly blown away.

Screen Shot 2017-02-26 at 17.45.10

Many thanks to Morag Hickman, Magda Durka, Cat Harris, Jinny Lofthouse and David Hing for helping put this article together.

Support our new film, the deliciously creepy OVERWRITE, here: Thanks!



Amazing, AMAZING news! New Tortoisebutler Film, OVERWRITE.


We  need your help in reaching the next exciting stage of tortoisebutler productions: making OVERWRITE (one of Pascoe’s mindbending scripts) the best film it can possibly be.  Read about it here:

You can help by spreading the word using the hashtag  #EverWantedToRobABank

…following the film on Twitter @OverwriteFilm (Twitter) and facebook

…and, if you are able to, by donating:

The lowest pledge is £1 – although for not very much more, your pledge
gets you a ticket to the screening and afterparty, which is going to be
absolutely EPIC.



Sound recording notes

This is a quick write up of the notes I made during filming a practice 48 challenge, hopefully others will find it useful.

Here’s the kit list with links to manuals, below it are notes on the recorders and the mixer:

Zoom H4N Audio recorder
This can accept two types of input into its line in ports: 1/4″ jack and XLR. It cannot accept line level inputs via XLR (although it can on the jack). This means if you’re using a pre-amplifier (we had a MixPre-D) it needs to output at mic-level rather than line, which is annoying.

This recorder *does* have internal limiter to avoid clipping

It is possible to do 4-track recording using both the internal and external mics, this might be useful for background/signal recordings for more mixing options.

One of the menu options is ‘monitor’, unlike the recorder doesn’t need to be pause-recording for this to be enabled.

Marantz PMD661

Unlike the H4N, this can receive mic or line level inputs; but it can’t limit them.

The latest version of the firmware seems to have dealt with whatever gremlin made it formate SD cards in such a way that any mac would instantly destroy them.

You can only monitor when in pause-record

Can only 2-track so if a clever signal/background rig would be wanted an extra microphone would have to be dedicated to


This thing has a lot of functions. My current favourite is trying to adjust the limiter (hold ch1 and ch2 whilst turning the headphones volume), if you miss one of the channel buttons (easy to do) you instead assign ch3/4, this will then mean you can’t get the tape return audio back which is *very* confusing.

Basically: this is a lovely machine, from a user-interface point of view it’s a train wreck. Be careful with those buttons.




A 15 second teaser we put together to promote our latest project!

Ever wanted to rob a bank? No? Ever worried you might… do it anyway?

OVERWRITE centres on a security guard who is having a very bad night. Someone is robbing his bank. Someone who looks exactly like him.

A horror-heist thriller, packed full of paranoia and terrifying impossibilities, OVERWRITE is a short film that documents the all-too-rapid disintegration of that guard’s reality along with his desperate attempts to claw back control.



A girl, her robot, an alien landscape.
When upgrading software could cost you more than your sanity.

A film about a lonely terraformer, made to the following criteria for the Sci Fi London 48 hour film challenge:
Dialogue: You can hide, but I’m coming for you, ready or not!
Prop & Action: A mug of a steaming liquid – a character sniffs the liquid, then pours it away.
Optional Science Idea: Mobile/Cellphone that controls body functions and appearance.