Car crashes, impalements, DIY mishaps. All these – and more – have featured in BBC One's medical emergency drama Casualty since it began in 1986. To cap its 30th series, the show has been filmed in a single shot, which, as Kevin Hilton explains, provided some challenges to the sound crew…
Long-running television series usually have a special episode to mark significant anniversaries. The trend recently has been for an all-action live production that tests the skill and resourcefulness of cast and crew alike. BBC medical drama Casualty has not followed this fashion for the climatic episode of its 30th season, but instead opted for something just as challenging: a story shot in a single, moving take featuring a wireless camera, five sound booms and 35 radio microphones.
Casualty is listed in the Guinness Book of Records as the longest-running emergency medical drama television series in the world. Created by Jeremy Brock and Paul Unwin to partly highlight the work of the NHS at a time when the Conservative government under Thatcher was planning cutbacks, the show first aired on 6 September 1986. Since then it has filled its regular Saturday night slot on BBC One with stories of horrific injuries sustained in often bizarre accidents, interspersed with the convoluted personal lives of accident and emergency (A&E) staff at the fictional Holby City Hospital.
The series was originally produced in Bristol before moving to purpose-built facilities at the BBC's Roath Lock Studios in Cardiff in 2011. The interior sets of the A&E department were designed to allow the actors and crew to move easily from one section to another, a facet that came into play during filming of the one-take episode. "It's a great set, very open," comments Tim Hunt, who has worked as a sound recordist on Casualty "for too many years to remember".
Hunt says the possibility of a live Casualty had been discussed over the years but when producers decided on a one-shot edition, he was still filled with some trepidation. "I was approached in June last year about doing it and spent the whole summer thinking 'this is big!’,” he comments. "I sat down one day and started planning it, realising that the big problem with one camera shot is that you're on a wide shot every time you move, so you see everything, which makes it difficult to film."
Doing things differently
A standard episode of Casualty is filmed using multiple cameras, with one production sound mixer on set, two boom operators and an assistant. Hunt knew this set-up would have to be expanded for this production, titled ‘One’, written by Paul Unwin. This was not only due to moving about the interior sets but also because the action begins outside the hospital with a big stunt sequence and follows an injured motorcyclist in the ambulance to A&E.
Taking the position of lead sound recordist, Hunt brought in a second production mixer, Brad Bower, to cover the ambulance scenes. Bower also assisted during rehearsals, adjusting gains and hiding microphones on set, as well as supervising the recording machines for the takes. Six booms were available to four operators – James Drummond, Abdul Amoud, James Abbay Bowen and Marc Walters – with four for interiors and two on exteriors. "The second exterior boom was if we needed to solve any shadows on a 360 shot," explains Hunt.
“The problem with one camera shot is that you're on a wide shot every time you move, so you see everything, which makes it difficult to film”
The intention was to match the sound of conventional Casualty episodes, which rely primarily on boom mic. But Hunt knew wireless systems would have to play a larger role than usual, particularly for scenes where it would have been difficult to position a boom without it being seen. "We do use radio mics, typically Audio Limited TX2440s, most often for sequences with the paramedics moving down long corridors from the ambulance bay," he says. "But we needed more on this shoot, as well as someone to monitor and mix the wireless feeds."
The incoming radio signals were handled by Scott Talbott, a BBC Studioworks sound supervisor usually based in London. Talbott worked in a flyaway control room built into the studio set by hire company Terry Tew Sound and Light, which also supplied 32-channels of Sennheiser SK 5212 wireless. The mix area was based round a 32-fader Studer Vista 5 console, feeding a RME MADI bridge connected to two JoeCo recorders, again provided by Terry Tew.
The wireless mic feeds went through the Vista 5, which was controlled by Talbott. Recording and playback in the control room were supervised by an assistant working with him, while a RF engineer looked after the racks. "All radio mics were isolated to the two JoeCos," Hunt comments. "Scott also recorded my monitor mixes of the booms and took all my ISOs. That meant we had duplicates and were not relying on one monitor recorder."
Hunt looked after two booms, recording the outputs on to a Sound Devices SD788 portable recorder through a CL-9 linear fader controller. "All six booms were recorded through the returns of the Studer," he explains. "We could listen to that and see how the extra radio mics were sounding with the booms. It was mixed pretty seamlessly – I was very happy with the mix."
This way of working allowed Talbott to add to the booms from his wireless feeds where appropriate. "As scenes of dialogue went through we could ascertain which lines I couldn't get with a boom," Hunt says. "Because Scott was quality monitoring he could bring in lines as necessary."
The Sennheiser SK 5212 body packs were fitted with DPA 4060 miniature mics. The four interior booms were Panamic poles supporting MKH 50 hyper-cardioid mics, connected to wireless systems using either PTX plug-ins or 2040 adapter leads. Exterior scenes used two MKH60 shotguns, also on 2040 transmitter links.
Body mics were worn by 27 of the performers in the episode, with one wearing a second mic and transmitter, Hunt explains, to "cover the dynamics of his performance". Some radio mics were built into the set or props for specific scenes. In one sequence two artists are singing in the background; a mic was hidden in the false ceiling above them while another pack and mic were attached to the bottom of a seat being hit with a rubber drum stick.
Wireless mics were fitted on to actors and their costumes by specialist sound engineer Zoe Milton, who was recommended by Terry Tew. Both had worked together on Woody Harrelson’s Lost in London, another example of single-take filming, albeit with a live element. Extra time was put aside for hiding mics in clothing, with Milton also checking each one in the fitting room on a Sennheiser EM 3732 live audio receiver to ensure clean feeds.
A wireless mic was also attached to the ARRI Alexa camera during the opening shots moving through the building. The Alexa played another part in the sound production by having the monitor mix output of the SD644 recorded on Track 1 of its audio tracks as a guide. Track 2 was used for a sync feed from the camera.
The ambulance scenes threw up some problems, especially in terms of how many crew members could be onboard with the actors. "I wanted Brad there as sound recordist but that wasn't possible because the camera crew wanted the focus puller in there as well," Hunt says. "Instead we rigged two Schoeps CCM 41 super-cardioid compact mics in the ambulance, hard wired to the SD664 hidden in a cabinet. That way we were able to cover the dynamics of the performance."
The ‘One’ episode of Casualty was in production from 3 April to 13 April 2017. "We divided the script into four and did a quarter each day," comments Hunt. "That meant we would see how the camera and the booms were working. After a full dress rehearsal we did as many complete takes as we could, changing things as we went. We ended up with four complete takes in three days, with takes 2 and 4 probably being the best. The idea was to do it without stopping."
BBC Casualty's single-take series finale ‘One’ airs on Saturday 29 July at 9:05pm.