Estelle Blaney is a non-canonical character who was created for the TV adaptation of The Ambassador's Boots in LWT's Agatha Christie's Partners in Crime. She is a friend of Tuppence from World War I days when they served together in the VAD (Voluntary Aid Detachment). She and some other VAD friends helped Tuppence rescue Tommy from trouble at Cicely March's cosmetic salon. See Poppy St Albans for detauls.
Estelle Blaney is portrayed by Norma West. This character does not occur in the original story. There, Tuppence summons the police and she joins them in rescuing Tommy.