Sisters Yvonne and Angela have been extreme cleaners for nearly two decades, and have worked on almost 6,000 jobs between them. This time, they are in London tackling the dirtiest flat they have ever encountered on the job. An elderly lady had been struggling to cope in a one bedroom flat. When the girls go to investigate they find a scene of heart-breaking squalor, with damp and mould throughout the flat spread by a leaking pipe that hasn't been fixed in years. The owner's dog has left faeces all over the floor, the furniture is rotting and food has been discarded throughout. What's more the bedroom has not been touched in 9 years.