The Hollywood actor Ed Harris, best known for his roles in Apollo 13, A Beautiful Mind and The Truman Show, stars in a series of TV commercials as a hotshot lawyer hired to prove the claims made for the car.
The success of the campaign, created by Lowe and breaking nationally on Thursday, is of crucial importance to the agency, which is currently involved in a review threatening its dominance of the £61 million Vauxhall account.
Each ad for the revamped Vectra takes the form of an episode in a US courtroom drama. It is part of a strategy of establishing the Vectra in an increasingly competitive market that has seen more than 55 car launches this year alone.
The new Vectra is regarded by Vauxhall as its most important launch for years. It replaces a seven-year-old model that had been left trailing the new versions of competitors in the upper-medium sector.
The ads begin with Harris urging his team to uncover all the examples of new thinking that have gone into the car. This is followed by the "trial in which Harris cross-examines expert witnesses and addresses the jury.
It ends with him facing a media scrum as the Vectra's case is "proved".
The spots were written by Tom Hudson, art directed by Steve Paskin and directed by Lenard Dorfman through @radical.media. Media is through Initiative.