[3] He was educated at The Manchester Grammar School,[4] then at New College, Oxford, Harvard, the Sorbonne University in Paris, and in Saint Petersburg – then called Leningrad – in Russia.
[citation needed] Sixsmith joined the BBC in 1980 as a foreign correspondent, reporting from Moscow during the presidencies of Mikhail Gorbachev and Boris Yeltsin and the collapse of the Soviet Union.
In December 2001, he returned to the Civil Service as Director of Communications for the Department for Transport, Local Government and the Regions, where he became embroiled in a scandal over the actions of Jo Moore.
Moore was a special adviser to the transport secretary Stephen Byers who had been the subject of much public condemnation for suggesting that a controversial announcement could be "buried" by being made in the wake of the September 11, 2001 attacks.
In 2015, he made a BBC television documentary, Ireland's Lost Babies, in which he revisited Philomena's story by travelling to the United States to investigate the Irish Catholic Church's role in an adoption trade which saw thousands of children taken from their mothers and sent abroad.
[13] In 2019, he published An Unquiet Heart, a historical novel based on the life of the Russian poet, Sergei Yesenin, and his stormy love affair with the actress Zinaida Raikh.
[14] In 2022, Sixsmith co-wrote The Russia Conundrum: How the West Fell for Putin's Power Gambit, with the former oligarch and liberal opposition campaigner, Mikhail Khodorkovsky.