Don Boyd’s “Lucia,” which Portman Entertainment has picked up for worldwide sale, marks the culmination of the latest phase in the British producer-director’s 25-year adventure in the indie screen trade.

“Lucia,” which Boyd wrote and directed, is the final film on a three-pic slate that his London-based banner Lexington Films has made over the past 18 months, entirely with private finance. The first, Roberto Bangura’s “The Girl With Brains in Her Feet,” was picked up by Alliance at last year’s Cannes fest; the second, Henry Herbert’s “Crossmaheart,” unveiled at this year’s event, is also being handled by Portman.

Now Boyd and Portman have started discussions on turning their ad hoc links into a more formal relationship that would involve Portman in financing Lexington’s movies. Having made three pics without any distributor input, Boyd feels it is time to take his operation onto the next level.

“I’m often described amusingly as a maverick and as a veteran, but even maverick veterans want to move on,” Boyd says. “I’m a true independent filmmaker, but we want to combine the experience and knowledge that we have gained in the past two years with Portman’s distribution expertise.”

Boyd’s producing career spans such arthouse highlights as the innovative ’80s movie “Aria,” in which grand opera collided with rock video, and several Derek Jarman pics. He set up Lexington with Henry Herbert and Stephanie Mills, and lined up a group of private investors willing to put up a maximum of $8 million for a slate of low-budget pics.

“Brains in Her Feet” weighed in at around $1 million, “Crossmaheart” (originally titled “Cycle of Violence”) tipped the scales at around $2 million, and “Lucia” used up much, but by no means all, of the remainder.

“Lucia,” in particular, is so unique that even Portman chief exec Tim Buxton concedes the pic would have been impossible to finance any other way. It’s a contempo version of both the Donizetti opera “Lucia di Lammermor” and the Walter Scott novel on which the opera was based. A group of people travel to Scotland to rehearse Donzetti’s opera, only to find their lives starting to eerily mirror the Scott story.

Pic uses young actor/singers, including Boyd’s daughter Amanda Boyd, who is a rising opera star. All the music was performed live on camera, with no miming to playback. The film’s radical intentions even extend to its technology — Boyd shot it on digital cameras rather than film, to achieve particular heightened effects. “Lucia” was produced by Mills and Alison Kerr.