There’s an excellent 90-minute film here; unfortunately, it runs for 170. Bertrand Tavernier probably intended “Safe Conduct” (“Laissez Passer”), a tale of French filmmakers operating under the strictures imposed by Nazi occupation, as a counterpoint to “Children of Paradise,” the 1945 epic-length classic about a theatrical troupe that actually was made in those conditions. And half of the story he’s chosen to tell, while hardly on the same level as Marcel Carne’s masterpiece, is nevertheless compelling and fascinating. The other part, however, is decidedly less successful, and together they make for a film that’s unduly distended, frequently confusing and ultimately rather dull. A sharper focus and active editorial shears would have made all the difference.

The script, based by Tavernier and Jean Cosmos on the reminiscences of the two major protagonists, alternates and intertwines the stories of Jean Devaivre (Jacques Gamblin) and Jean Aurenche (Denis Podalydes). The former is an assistant to director Maurice Tourneur (Philippe Morier-Genoud) at Continental Films, now being run by the sophisticated, suave Dr. Greven (Christian Berkel). (Maurice, who’d worked very successfully in America from 1914 to 1926 before returning to France, was also the father of Jacques, perhaps best known for his low-budget horror collaborations with Val Lewton but also for such later films as “Out of the Past” and “Night of the Demon.”) He’s also a devoted husband and father, a former bicycle racer who can still peddle long distances, and–as it turns out–a patriot, willing to take considerable risks to assist in the struggle against the Nazis. Aurenche, on the other hand, is a distinctly faithless spouse who refuses to work for a German boss and spends most of his time, it seems, cavorting with his mistress, actress Suzanne Raymond (Charlotte Kady) as well as several other women.

So long as “Safe Passage” concentrates on Devaivre, it’s genuinely interesting and often touching. The director’s dedication to his family and to Tourneur makes him a truly admirable figure, and his hesitant service to the resistance in the final reels is exciting, with moments of mordant humor mixed in with the tension. And the sad-faced Gamblin is quite successful in capturing the fellow’s ordinary-man heroism. If Tavernier had concentrated his attention on telling Devaivre’s story cleanly and concisely, he would have had a winner. But he’s been diverted by the desire to fashion a complex Atmanesque sort of narrative, with intricately interlocking plot strands and large numbers of colorful characters almost carelessly thrown together; and he was also apparently led off course by his personal attachment to Aurenche, who wrote a number of Tavernier’s films before his death in 1992. But he hasn’t Altman’s touch in keeping the various threads clear, nor has he been able to make Aurenche a fully-developed or rounded figure. The result is that the film is frequently muddled, drifting into what amount to rather tedious digressions. And even when it takes up an ancillary story strand with potential dramatic impact–like the difficulties that writer Charles Spaak (Laurent Schilling) got into because of Devaivre’s theft of German documents–the picture doesn’t dramatize it with sufficient force. Throughout, moreover, the dialogue is curiously flat given the creative genius of the people being depicted.

“Safe Passage” is an accomplished production, effectively recreating the ambience of occupied Paris with expert production design and widescreen cinematography (by Alain Choquart) that emphasizes dark colors and shadows to impart a feeling of gloom and desperation. It also makes good use of clips from actual films of the time, even if the identity of the sources will mystify all but the most devoted movie buffs. But despite all the atmosphere and Tavernier’s obvious devotion to his subject, the picture’s clumsy construction and variable effectiveness make it a chore to sit through. Unless you’re one of those people who consider half a baguette better than none, you’d be well advised to take a pass on it.