McSweeney, left, is married to the new Labour MP for Hamilton and Clyde Valley, Imogen Walker. They both started out in politics in south London, serving together on Lambeth Council. And she’s a former actor, whose credits include a role on Taggart alongside Alex Norton and Blythe Duff.

The new chief of staff is Starmer’s political mastermind and he ran the election campaign which delivered a landslide victory for Labour. However, the party actually got fewer votes than it did in 2019 under Jeremy Corbyn and in reality the key factor was disgruntled English Tory voters either staying at home or switching to Reform.

Born in Ireland, McSweeney is said to divide his time between Westminster and the home he shares near Lanark with Walker and their young son. He is said to be far more politically astute than Gray, who is being blamed for tone deaf policy decisions such as axing the universal winter fuel allowance.

Speaking to the Sunday Post, Walker insisted that her husband’s powerful role had nothing to do with her selection for the seat. She said: “I’m a candidate, he’s the campaign director. I don’t speak for him and he doesn’t speak for me. I’m doing this on my own merit, on my own strengths, and I’m going out and talking to people on the doorstep.”
Imogen Walker is said to be the Chancellor’s ‘eyes and ears’ in Westminster.

But critics including the SNP say she was “parachuted” into Hamilton and Clyde Valley after spending her political career in south London and she only narrowly won the selection against local contender, Gavin Keatt, by 62 votes to 55. The political journalist Michael Crick said: “Keatt actually won strongly at the hustings meeting, but Walker took the nomination by winning decisively with online votes.”

A philosophy graduate of Edinburgh University, she won the seat comfortably from the Nats with a majority of 9,472 and was quickly promoted as Parliamentary Private Secretary to Rachel Reeves, Chancellor of the Exchequer.

McSweeney grew up near Macroom in Co Cork and moved to London as a teenager, before joining Labour in the wake of the Good Friday Agreement. His family has connections to Fine Gael, Ireland’s centre-right party – his aunt Evelyn McSweeney was a Fine Gael councillor, and his first cousin Clare Mungovan was one of former Taoiseach Leo Varadkar’s top advisers.

Described as a “workaholic”, he is hated by many on the left of the Labour Party, having been instrumental in propelling Starmer into power and then leading the purge against Corbyn and his supporters.