Kevin Langdon Ackerman had a good lead, so he left his home in the Los Angeles neighborhood of Beachwood Canyon on a Tuesday morning in August and drove 18 miles northwest to Sylmar, Calif.

He guided his metallic black BMW off the 210 and up the winding road to the top of Little Tujunga Canyon; on the right side, Middle Ranch, an equestrian facility and popular wedding venue, on the left, multimillion-dollar estates, everything surrounded by the mountains of the Angeles National Forest. Eventually he reached his destination, a Santa Fe-style home built in the early 1900s.

There he met his contact, Caroline Debbané, who took him not through the front door but around to the back of the property. There, a modern lock code opened the swinging cellar doors, and the two descended a flight of concrete steps to the bunker.

One entire wall had built-in wine turrets, with dusty bottles of wine and champagne lying on their side. Another wall acted as a liquor cabinet, with more bottles of bourbon, Irish whiskey and rum, untouched for over a half century. Mr. Ackerman had found the booze collection of Cecil B. DeMille, the legendary director and producer.

“I’m thinking, ‘Holy crap! I want this, and I need to get this,’” Mr. Ackerman said. “In my mind, this was born of and ultimately the fruit of me being incredibly vigilant over the last eight years.”

Mr. Ackerman, himself a filmmaker by trade, is also a dusty hunter: an antique collector who only searches for still-sealed bottles of vintage alcohol, usually American whiskey. Discussion of dusty hunting, and the use of that exact term, appears on the internet around 2007, mostly on whiskey enthusiast blogs and message boards, such as Straight Bourbon. (Collectors of vintage nail polish, chronicled by The Times in 2014, are also considered dusty hunters.)

Though this is a fairly new hobby, it is one already facing its end days, as there are simply fewer and fewer undiscovered bottles still out there to find. Mr. Ackerman took up the quest in 2012, after coming across an online article about a group of friends who had specifically flown to Kentucky to search liquor store shelves for old bottles of bourbon from the much lauded but by then defunct Stitzel-Weller Distillery.