Inspector Lewis took on one of his toughest-ever assignments yesterday - saving Oxford from a controversial new housing development.
Actor Kevin Whately, who plays the popular screen detective, took a break from filming in the city to make a passionate plea to preserve the area alongside the Oxford Canal in Jericho.
Last year, Oxford City Council turned down Spring Residential's plans to build 54 flats and a boat repair berth at the former Castle Mill boatyard site.
Yesterday was the last day of the planning inquiry held after the developer's appealed against eh council's decision.
Last week, Oxford author Philip Pullman led a protest by 200 residents before the inquiry opened and yesterday Mr Whately called for the development to be refused.
After arriving at the Town Hall, in St Aldate's, to shoot a courtroom scene for a new episode of the Inspector Morse spin-off Lewis, he said: "We have often filmed scenes for Inspector Morse and Lewis next the canal in Jericho and it means a great deal to us.
"This inquiry is the last chance for residents to have their say on this issue and I'm delighted we are filming in the Town Hall on the last day of the inquiry.
"This is not just sentiment - the development would harm views from the canal, which should be used more and more these days for carrying freight.
"I hope the inspector turns down the developers."
Last week, Mr Pullman, the author of the His Dark Materials trilogy, which features Jericho, compared its canalside with Venice, and urged planning inspector Ava Wood not to alter the street scene with "one stroke of the planner's pen".
Adrian Arbib, who has led the campaign to preserve the boatyard facilities, said: "Their involvement shows the value of Jericho to people in Oxford - they don't want this massive development spoiling the area.
"Spring's designs don't respect the heritage of the area in any shape or form and consultation with the community before this inquiry was sub-standard."
The hearing is the second public inquiry into the future of the boatyard site, after an earlier proposal from Bellway Homes was rejected three years ago.
Protesters are hopeful the latest designs will be rejected - partly because the developer has only offered to provide 35 per cent affordable housing, rather than the 50 per cent the city council requires for new development.
Oxford West and Abingdon MP Dr Evan Harris told the inquiry: "Local councillors and I see heartbreaking cases of people who cannot afford to stay in Oxford, where they grew up or where they work, or where their family is.
"That's why we expect the council to hold the line on 50 per cent - to secure the building of houses for families and individuals who need them."
The planning inspector's decision is expected to be announced before the end of the year.