The 'Grisaille Fleurs de Lys' are a group of four autonomous artworks in stained glass: drawings in lead and mouth-blown glass, framed within an irregular border of solid lead or coloured glass. Each work adapts the motif of the fleur de lys to form a ‘portrait’ of Brian Clarke’s friends and collaborators, the architects Jan Kaplický, Oscar Niemeyer, Norman Foster and Zaha Hadid, after whom each work is named.

Speaking on the works, Clarke said in 2021:

'These are part of a quite large group of paintings, drawings, tapestry and stained glass projects and pieces in which I have taken this medieval heraldic symbol and used it as a route map to journey through my own preoccupations and interests. Considering the design perfection of the millennium-old original fleur de lys, my works are like the modern remains or wreckage of ancient masterpieces. I’m involuntarily drawn to the symbol, and it has served me as a metaphor, model and springboard for spontaneity for years.'