Agency Office to Close After Losing Infiniti : Advertising: Hill, Holliday in Marina del Rey will lay off 120 as Nissan’s luxury car line switches its account.

The Marina del Rey office of the ad agency Hill, Holliday, Connors, Cosmopulos--which employs nearly 120 people--will lay off its entire staff and close its doors after executives were told Wednesday that their only major client, Nissan’s Infiniti luxury car line, was stripping the firm of its ad business.

The $75-million ad account--as well as Infiniti’s public relations business--was handed to the Venice office of Chiat/Day/Mojo, which already handles Nissan USA’s corporate account. The switch is a huge boost for Chiat/Day, which last week lost its $60-million American Express credit card ad business.

William R. Bruce, vice president and general manager of Infiniti, said in a statement Wednesday that Infiniti made the change to find “efficiencies” in its advertising costs and “to establish a distinct brand image that is mandatory of a luxury division.”

All of this comes at a time when a number of auto makers--their sales pummeled by the recession--have been scrambling to improve their images.

Last week, BMW put its $65-million account up for review. Several weeks ago, General Motor Corp.’s Oldsmobile division placed its $140-million account into review. And the makers of Jaguar and Mercedes-Benz both selected new agencies earlier this year.

On Tuesday, Tokyo-based Nissan Motor Corp. announced a $178-million loss for its fiscal first half, the first loss for the company in its 41-year history.

Since it was introduced four years ago, Infiniti has been a car in search of an image.

The initial teaser campaign showed pastoral scenes of rocks and trees that talked about the Zen of driving--but didn’t show the car.

Although that campaign was much talked about, it was also ridiculed by ad critics and even parodied on NBC’s “Saturday Night Live.” But the bottom line--its sales--have been disappointing.