The Louis Heel

An early 18th century style originating in France and then called the Pompadour. It went through several refinements until it fell out of favour around the time of the French revolution.
It was reintroduced in the 1870s, renamed the louis and remained in fashion until about 1930. There have been several revivals since.
They were made of wood and covered either in fabric or leather or sometimes just painted until the 1920s when celluloid studded with rhinestones made an appearance.

English embroidered leather c1780-90, sturdy and sensible

Silk with a slim 'Italian' heel that supports the arch

Silk wedding shoes c1886, English

Gold kid with a steep arch to shorten the foot, 1880-90

Hellstern Paris 1920s

Delman USA c1935

Manolo Blahnik 1995

Smartphone

Hello Chief.

Technology began to play a part in the construction of shoes in the early 50s with the development of the stiletto heel using a thin spike of metal to obtain ulitmate slimness.
By the end of the 60s heels came in all shapes or famously there were shoes with no heels at all but none of them went so far as Maxwell Smart's shoe phone.

Get Smart satirised the TV spy genre, itself set off by the success of the Bond films. No self respecting TV spy was without his homing transmitter hidden in the heel of his shoe (or suicide pill). Needless to say the shoe was only worn when the story called for Smart to answer the phone, like James Bond's cars overloaded with guns, ejector seats, rocket launchers and oil slicks, there was no room for the engine - or foot. However Smart's main problem with the device was getting the operator to put him through.

Agent 86 Maxwell Smart

Maxwell receives a call - YouTube

Rayne Spotting 3: The Avengers 1968

Rayne continued to provide shoes for The Avengers show. These gold glitter mules worn by Tara King in a publicity still for the series also appeared the the episode SPLIT. She carries them into Steed's apartment in the tag scene and the logo is easily seen.

John Steed & Tara King for The Avengers 1968