The second series of The Crown is to document the romance between Princess Margaret and Lord Snowdon, portraying him as a charmer who harbours “dark secrets”.

The lavish Netflix series returns on December 8 and while the Queen remains at its heart, the arrival of a young Antony Armstrong-Jones will provide some of the most involving storylines.

Snowdon, who died in January aged 86, enjoyed what his obituarist described as “an extraordinarily complex love life”.