TELLURIDE, Colo. – My immediate takeaway from Jason Reitman’s “Labor Day,” which kicks off the Telluride Film Festival this afternoon at the annual patrons screening, was that it was an unexpected mature step for the filmmaker who has offered up such self-aware films as “Thank You For Smoking,” “Juno,” “Up in the Air” and “Young Adult.” There isn’t a whiff of that tone here whatsoever. The edge that has defined Reitman’s work has been set aside while a more refined, lived-in aesthetic has taken hold.

Those other films had a very distinct voice, and they were all great movies. This one is told in a completely different voice, however, and I guess that’s what I mean when I say the results are unexpected; it’s unusual to see a filmmaker tap another perspective on narrative so confidently this early in a career. Reitman is still under a decade in features, after all.

The work I was most reminded of was Clint Eastwood’s from the early-90s. Indeed, “Labor Day,” which is based on the novel by Joyce Maynard, feels like it was baked in the same oven as “A Perfect World” or “The Bridges of Madison County.” It sits with its characters, measured, patient with them.

The drama centers on Kate Winslet as Adele, the mildly reclusive mother of 16-year-old Henry (Gattlin Griffith). The two are taken captive by escaped convict Frank (Josh Brolin) in their New Hampshire home over a Labor Day weekend in 1987 (making the film’s debut this particular weekend all the more apt). But Frank isn’t what he seems to be and as we learn his story, the reason for Adele’s emotional neurosis and the impact the weekend has on Henry, the film becomes a story of family and, more profoundly, the burden of responsibility a young person has to the emotional well-being of a parent.

The movie is a highlight for Reitman and might be his most deeply felt work yet. It’s full of texture, less interested in telling you a story than showing you one, by which I mean, this isn’t a movie — like “Up in the Air,” like “Thank You for Smoking” — that’s actively looking for a place to land. It’s more reserved than that. Rich though the film may be, it doesn’t have the swagger others have come to expect of his filmmaking, which was already assured, and it’s an incredible step in a different direction for the 35-year-old director.

That richness is felt across the work of Reitman’s crew, as well. The art department in particular deserves singling out. The decoration of these modestly period sets really establishes a sense of time and place that feels familiar and real. Eric Steelberg’s photography has never been so lush and evocative. Editor Dana Glauberman gets to play with more than usual in the film’s assemblage and Rolfe Kent’s score is delicate and appropriate.

The film could certainly figure into the awards season, particularly in the lead actress race; Winslet’s performance isn’t outwardly showy but it’s very specific, nuanced and sublime. And Brolin, who is currently set for a supporting actor push by the studio, provides a valuable spark throughout. His presence is felt even when he’s not on screen.

It will, however, be interesting to see how a release date very late in the year affects this one. It’s set for a limited bow on Christmas Day, with an expansion in January. That gives it room to breathe at the box office away from the November-December glut, but it could be a little late to grab the Academy’s attention as members scramble to catch up with everything as the January voting deadline looms. And as we’ve mentioned, Paramount has Alexander Payne’s black-and-white indie “Nebraska” (also playing Telluride) and Martin Scorsese’s high-key dissection “The Wolf of Wall Street” to work with as well.

“Labor Day” falls somewhere in between those two extremes and could resonate in the middle of the road. That is not, however, to say the film itself is “middle-of-the-road.” On the contrary; it’s a fresh step for Reitman on a separate path, and the growth won’t go unnoticed. It’ll be interesting to see how the masses take to it next week at the Toronto Film Festival.

Check back later tonight for another take on the film from Greg Ellwood.

“Labor Day” arrives in limited release on Christmas Day.