Thin Ice, the third episode of Doctor Who Series 10, was a significant one for The Model Unit. Not only was it our first Twelfth Doctor episode (continuing our run of work with each of the four actors to have played the lead role since the show returned in 2005) but it is also one that allowed us to work with a colleague whose last contribution to the show was during Sylvester McCoy’s last season way back in 1989.
We were contacted in August of 2016 by Line Producer Steffan Morris, who asked if we could provide a couple of key moments in the story where the Doctor, clad in a period diving suit, crashes though the ice covering the Thames and sinks to the river bottom.
Although an underwater shoot had already been scheduled as part of the production, the actual moment of impact on the ice, and the subsequent shots of the Doctor sinking, were considered too tricky to achieve as a full-sized stunt, and so we were asked if it was something that we thought could be achieved realistically as a model shot.
“I was certain that we could give the production what they wanted,” explains Model Unit Supervisor Mike Tucker, “and I knew that a moment not dissimilar to this one had been achieved in miniature for James Cameron’s film ‘The Abyss’. I was fortunate in that filmmaker Berton Pierce had gathered a huge amount of photographic material from that film when he was shooting his ‘Sense of Scale’ documentary, and he very kindly provided several great images of the puppet used by Cameron’s effects team for me to take to the planning meeting in Cardiff. Those pictures were a great help in convincing the director and producer that what they wanted to achieve was possible.”
Following that meeting it was agreed that The Model Unit would provide a 1/3rd scale puppet of Peter Capaldi’s Doctor in the diving suit and a large section of ice sheet, with a breakaway section, to be filmed at the Real SFX water tank at Pinewood Studios Wales as part of the wider underwater shoot.
With less than a month until the shoot Model Unit regular Alan ‘Rocky’ Marshall was given the task of sculpting the main body of the puppet and constructing the internal armature. Working from photographs provided by costume designer Hayley Nebauer a lot of the detail was sculpted into the clay original, with the aim of avoiding potential problems with sections detaching once the puppet was submerged in water.
The internal armature – heavily weighted with lead sheet in order to ensure that the puppet would sink – was made in such a way that the pose could be adjusted in order to match whatever the main unit eventually shot. A two-part plaster mould was then taken from the sculpt and a latex and polyfoam form produced. Care had to be taken to ensure that the armature was carefully positioned within the mould before pouring the foam in order to ensure that elbow and knee joints ended up in the right place.
Whilst Rocky was dealing with the torso, Mike concentrated on the construction of the diving helmet. The helmet was fashioned from plaster, detailed with scale rivets, and then moulded in silicone on order to produce a hollow, fibreglass version. Because of the large size of the face plate aperture, there was a distinct possibility that the head inside might be visible – particularly since the production had asked for the interior of the helmet to be illuminated – and so Mike turned to a colleague from the past.
“Stephen Mansfield, working alongside Susan Moore, had been responsible for many of the monsters during Sylvester McCoy’s tenure as the Seventh Doctor. He’d sculpted some great creatures during that period – the Haemovores, the Destroyer, Fifi – and I recalled how impressed I’d been with the portrait head of Edward Peel that he’d created for the ‘melting face’ sequence in ‘Dragonfire’. Even though our puppet was only going to be seen in one or two very brief shots, it was clear that a key part of its believability was going to be its likeness to Capaldi, and given that Stephen is so talented at capturing a likeness, I asked him if he was up for doing the sculpt for us.”
Stephen jumped at the chance, and began sculpting a miniature portrait head of Peter Capaldi that could be mounted inside the scale fibreglass helmet.
With all the disparate parts of the puppet underway, Mike moved on to the construction of the ice sheet. Constructed over a timber frame, the ‘ice’ was acrylic sheet, textured with resin and tissue, with an aperture in the centre large enough for the puppet to fall through. The breakaway section was cast in wax, with multiple sections produced to allow for several takes.
Once the sculpt of the head had been delivered, it was moulded in silicone, cast in polyurethane resin, painted and fitted to the body of the puppet. Final dressing could now be added – a leather belt with a soldered brass buckle, straps and lacing on the sleeves of the suit and boots and scale wing-nuts on the collar. Two sets of gloved hands were sculpted allowing us some variation in look between shots. The long, flexible air line trailing from the back of the suit was constructed from extruded plastazote rope.
Although we had initially hoped that the helmet could be vacuum-plated to better match the highly polished metal of the full sized costume, timescales forced us to resort to a spray paint finish instead.
The final task was to fit a hanging point to the top of the helmet, so that the puppet could be suspended over the ice sheet.
Filming took place in Cardiff on the 22nd September 2016, the model shoot being combined with a stunt sequence also requiring use of the Real SFX tank. Mike and Rocky were joined by veteran FX designer Colin Mapson for the shoot, and the morning was spent prepping the miniature ready to turn over after lunch.
We were fortunate to have an an excellent rigging crew who had already prepped the tank for us in advance, and once the live action stunt sequence had been completed the miniature ice sheet was attached to a scaffolding frame and positioned so that it was just touching the surface of the water.
Once the acrylic sheet was in place, gangplanks were slid across it so that we could set the breakable wax ‘ice’ sections over the pre-cut hole, and position the puppet above. Release of the puppet was triggered via a twelve volt ‘bomb release’.
High speed underwater photography for the sequence was provided by specialist DoP Rob Franklin and his dive team.
Director Bill Anderson and Producer Nikki Wilson oversaw the shooting, and we ended up filming over a dozen takes, revising and refining the shot each time, until Bill was happy that we had a shot that would work within his edit. The puppet was then reposed for shots of it drifting slowly down through the water towards the river bottom.
“Even though the shots form a very small part of the episode, it was a pleasure to get an opportunity to work on an episode of Doctor Who once more, especially as it allowed us to reintroduce sculptor Stephen Mansfield to a show that he had last worked on over twenty seven years ago.”
Model Unit Crew:
Model Unit Supervisor: Mike Tucker
Senior VFX Technician / Sculptor: Alan ‘Rocky’ Marshall
Senior VFX Technician: Colin Mapson
Portrait Sculptor: Stephen Mansfield
Director: Bill Anderson
Producer: Nikki Wilson
Line Producer: Steffan Morris Underwater
DoP: Rob Franklin
Grip: Sam Reeves
Gaffer: Mark Hutchings
Best Boy: Andy Gardiner