All surviving negative and positive materials for “Hello Pop” — a Three Stooges short in early two-color Technicolor that MGM released in September, 1933 — were believed destroyed in a 1967 vault fire at the Culver City studio (that also claimed Todd Browning’s “London After Midnight” and most outtakes from “The Wizard of Oz.”) Fifty-five years later, the Vitaphone Project — a New Jersey-based group whose mission has expanded from reuniting long-missing soundtrack discs for early musical shorts with mute prints in archives to worldwide searches for missing features and shorts from the post-Vitaphone era — was contacted by an Australian film collector asking if “Hello Pop!” was a lost film. Indeed, it’s the only short or feature with the prolific Stooges not known to exist in any form.

The Vitaphone group’s Ron Hutchinson, contacted Ned Price, head of preservation at Warner Bros., which holds the rights to the pre-1986 MGM film library, and made arrangements for the two-reel short (on highly flammable nitrate film) to be repatriated to the United States for restoration and preservation.

Hutchinson will introduce the film at 3 p.m. Sunday as well as 3 and 6:30 p.m. on Monday at Film Forum in Manhattan as part of a program called “Lost… Now Found.” The show also includes “Gobs of Fun” (1933), a Vitaphone short with Shemp Howard, an original member of the Stooges who rejoined the team following a long solo career after his brother Curly was sidelined by a stroke, as well as “rare examples of early Technicolor” from George Eastman House.” I’m particularly interested in seeing a newly-struck print of “Technocracy and You,” the only short that humorist Robert Benchley made at Universal Pictures, which as far as I can tell has been unseen since it was released in 1933.

Directed by Jack Cummings (who later headed a unit producing musicals at MGM) and featuring songs by Irving Berlin with incidental music by Dimitri Tiomkin, the backstage musical “Hello Pop” features the Stooges’ then employer, Ted Healey (who they split with the following year when the Stooges began their long affiliation wth Columbia Pictures), sometimes foil Bonny Bedell, and, as you can see from this still, Edward Brophy — as well as Henry Armetta, singer-dancers Vivian and Rosetta Duncan, as well as the Albertina Rasch dancers (including Ann Dvorak).

“Hello Pop” is part of a cache of hundreds of hundreds of early sound features and shorts that were acquired by a group of young Australian collectors when distributors cleared their shelves of nitrate prints in the 1960s. The collectors — who paid drivers of garbage trucks to deliver the prints to their homes instead of landfills — are now mostly in their 80s and are working with the Vitaphone Project to catalogue, repatriate and restore films that are not known to exist in this country. Australia and New Zealand have been especially fertile areas for rediscovery of lost films in recent years, as the American studios found it too expensive to have prints shipped back from such remote areas.

“It’s a lesson to never give up hope on supposedly lost films,” says Ned Price of Warner Bros., who has worked with the Vitaphone Project on a number of restorations. “The collector who held ‘Hello Pop” didn’t even know it was a lost film because he doesn’t have access to the Internet.”

Price says a “deep search” of Warners’ own vaults recently turned up “a few” two-color Technicolor negatives for features that were only believed to exist in black-and-white versions created for the early TV market (he didn’t disclose any titles). “The belief was that we didn’t keep any of them. But you can’t take anything at face value.”