In the last of the quarter-final heats, the designers transform two rooms each in glamorous 1930s art deco flats. A possible asbestos outbreak means work is halted for one of the designers. Will they complete their rooms on time? Meanwhile, the other designer might be going too far off brief with a butterfly-inspired effect which dominates heavily throughout the living room. Architectural historian Tom Dyckhoff takes us back in time and shows us that 1930s Streatham, meaning 'Hamlet on the Street', was one of London's most forward futuristic glamorous neighbourhoods.

In the penultimate show of the series, the two designers have to transform two rooms in pretty thatched cottages in Ashby St Ledgers. Both designers are tasked with transforming a living room and a dining room. Judging them are regulars Kelly Hoppen and Daniel Hopwood and guest judge Michelle Ogundehin, editor in chief of Elle Decoration. Both designers unwittingly use the same colour but will this help or hinder their chances with the judges? One designer is seriously out to impress, but will the use of a very detailed and overpowering matching blue print for wallpaper and curtains impress the homeowners or put them off? Will Michelle Ogundehin agree with Daniel and Kelly or put a cat amongst the pigeons? Meanwhile, Tom Dyckhoff discovers the beauty and origins of olde world picturesque country cottage living and the characteristics of thatched dwelling.