Continuing its Russia season to mark the centenary of the October Revolution, BBC2’s drama-documentary looks at the three men who created an entirely new political system – Lenin, Trotsky and Stalin.

In just six months, they had turned the largest country on Earth into the first Communist state.

Historians and writers still debate to this day whether it was a triumph of people power, or a violent coup d’etat. Juliet Stevenson narrates.