It is the preferred drinking establishment of north London's intelligentsia – David Miliband and Jon Snow among them – and celebrity regulars include Harry Enfield, Jamie Oliver and Sienna Miller.
The Engineer, the independent Primrose Hill watering hole considered one of the founding fathers of the gastropub movement, is under threat of new ownership after its landlord, Mitchells & Butlers, issued notice to the proprietors that it planned to take over the pub next year.
The M&B chain, whose franchises include Harvester, Toby Carvery, All Bar One and O'Neills, intends to manage the distinctive pub as part of its estate of 1,600 high street operations when the 10-year lease extension expires at the end of this year.
The news has been greeted with derision by locals and triggered a campaign spearheaded by the north London celebrity circuit.
"London is a series of villages for which the pub is the last point of contact," Jon Snow said last night, promising to "rally the intelligentsia".
"The idea of doing a Blitzkrieg and neutralising old independent boozers in favour of a dilation of identikit offerings akin to Piccadilly Circus is very sad indeed."
The television presenter Dermot O'Leary described The Engineer as a "local institution". "Its appeal is something that a pub chain, no matter how hard it tries, simply can't replicate," he said.
"I've lived in Highbury for six years and we have a perfectly decent chain pub that no one goes to, because there is no soul, no heartbeat, and no identity to it."
Mr Miliband described the move as "really stupid". He said: "Louise [his wife] and I have been going to the pub for over a year." He wished the campaigners luck.
Harry Enfield, who famously hosted lunch at The Engineer on his wedding day, said: "Without their personal input and the dedication of their team, I'm certain there will be a slow and inevitable decline in standards and staff until it returns to the lousy pub it used to be. The landlords think they can swipe the profits and keep the magic."
This plight of The Engineer is the latest headache for the bohemian residents of Primrose Hill, who pride themselves on resisting the homogeneity of the high street.
The suburb has one of the lowest ratios of chain stores to independents in the capital. Recent plans to open a Starbucks struggled to take off, while the branch of Café Rouge that opened in the area lasted less than a year.
In 1994, the current proprietors, Abigail Osborne and Tamsin Olivier (the daughter of Sir Laurence) took the lease of the pub, then a rundown London boozer, off the hands of Bass Taverns. During their 17-year management, they have championed a menu sourced from organic suppliers in Islington, Sussex and Devon. Tracy Macleod, a restaurant critic for The Independent, said yesterday: "The move from independently sourced suppliers to what at worst could be boil-in-the-bag catering could certainly be felt by the custodians of North London's finest gastronomy."
A spokesman for Mitchells & Butlers defended the takeover plan, promising to maintain the pub as a "distinctive, individual and characterful London landmark".