“It’s a Wonderful Life,” which is being shown in a new 35mm print at the IFC Center in Manhattan through December 27, is the most beloved of all Hollywood Christmas movies, though the myth persists that it’s a cozy celebration of traditional family values and small-town American life. Certainly, Frank Capra’s drama about a man who has sacrificed his ambitions to serve his community, is a masterpiece, and one that makes for perennial holiday viewing, but it’s an unusually dark and disturbing one.

The progress of the dutiful mortgage lender George Bailey (James Stewart) is marked by creeping existential angst, which explodes during his nightmare, the film noir-within-the-film. This effaces his existence more completely than he has effaced it himself by staying in Bedford Falls and succumbing to the maternal needs of his wife, Mary, the only character in the film who maintains her integrity. Steered by the angel Clarence (Henry Travers) in the terrifying fantasy sequence, George is horrified by the hyperbolically sleazy and violent urban dystopia that Bedford Falls would have become had he never  been born.

Mary was played, of course, by 25-year-old Donna Reed, whose luminous performance should have won her a Best Actress Oscar nomination in 1946. The calm, feminine center of the film, she is first seen as 18-year-old Mary Hatch who transfixes George with her beauty at a 1928 high-school graduation party and then dances the Charleston with him before tumbling into the swimming pool. The climactic moment of their courtship, following George’s futile attempt to reject Mary because he knows marriage will keep him in a town he so desperately wants to leave, culminates in their desperately steamy clinch as they talk on the phone to a friend, Sam Wainwright (Frank Albertson) — it’s one of the most erotic scenes in a mainstream American picture.

Reed is remarkable, too, in the later scene when George, fearing the collapse of the building and loan he has fought to protect from the clutches of his nemesis, Mr. Potter (Lionel Barrymore), breaks down and berates the children she has burdened him with, love them though he does. As George rages, Mary watches and assesses his anguish, sympathetic to his plight, but finally gathers the children round her and asks him why he is torturing them. It is screen acting of the highest caliber.

There’s little doubt that playing Mary Bailey eventually led Reed to her other iconic role, that of the upper-middle-class homemaker Donna Stone in “The Donna Reed Show,” which ran for 275 episodes on ABC from 1958 to 1966; Season 4, containing 39 episodes, was released on DVD this week. Among the roles Reed played after Mary and before taking on Donna was that of Lorene, the sultry, sophisticated Hawaii-based prostitute in "From Here to Eternity," a brilliant stroke of counterintuitive casting. Her performance won her the 1953 Best Supporting Actress Oscar.

A few days ago, I talked about Reed’s contribution to the film with Mary Owen, the youngest of the actress’s four children with the agent-turned-producer Tony Owen, and the keeper of her mother’s flame.

Your mother was at MGM when she was cast in “It’s a Wonderful Life,” which was made independently by Capra. How did her casting come about?

Capra originally wanted Jean Arthur [Ginger Rogers and Olivia De Havilland were also considered] because my mother was virtually unknown at that time. She’d been in a lot of MGM B movies that soldiers in the war had seen, and the studio was in the process of making her a star. Capra had been impressed with her in John Ford’s “They Were Expendable” [1945] and had thought of her as Mary Bailey. Then he saw her on the MGM lot and knew immediately that she’d be right for the role.

Was he drawn by that wholesome quality she often exuded?

I think she represented to Capra  the sort of simple, country woman who would want to be with one man all her life. She had been brought up on a farm in Iowa, of course, and she made it look so easy. But she mentioned to me that she never worked as hard on a film as she did on “It’s a Wonderful Life” and that it was the most satisfyimg experience of her career. She learned so much on it.

There’s a sense in which George is resentful about his love for her because he knows marriage will stop him seeing the world. But he can’t resist his desire for her, as we see in the phone scene. Did she ever talk to you about it?

Not specifically, but I know there were a number of factors outside the film as well as inside the film that affected that scene. One of them was World War II. Capra and Jimmy Stewart had been gone from Hollywood for five years. Stewart had been decorated as a fighter pilot. Capra had worked on the “Why We Fight” films, and had also been privy to all the atrocity footage from the war, both from the Pacific and European theaters. “It’s a Wonderful Life” was their first film after the war. They were different people than they had been, and no longer had the same connection with Hollywood. There was a lot of insecurity on the set — especially Stewart, who was depressed. Lionel Barrymore apparently sat him down and had a talk with him to straighten him out a bit.

When it came to do that scene in the schedule, Stewart said, “No, no, no, I’m not ready.” And this went on for quite a few days until finally he said, out of the blue, “O.K., I’m ready to do that scene.” They had to scramble to get ready, but, of course, my mother was prepared. George is so ambivalent about Mary there. His anger has been building up because all of his plans have been thwarted, but also I think Stewart’s own feelings of not being connected to Hollywood and his uncertainty about whether he was still a talented actor added to that. You can see how pent up he is. They actually did that scene in one take. Capra said, “Cut.” But some dialogue was left out and the script supervisor said, “Guys, you’re missing all these lines,” but Capra said it didn’t matter. They had to edit the scene, though,  because it was considered too racy.

George’s nightmare was shot like a film noir, wasn’t it?

Yes, there are some beautifully dark, scary scenes in that sequence. Some people dislike the film because they think it’s too Capra-corny, but you’ve got to look at that part of the film to understand it. It foreshadows how America would be shown in many movies after the war. It may have sprung from Capra’s unconsciousness. I know he felt differently about the country after the war.

Your mother is the timid, virginal librarian whom George scares in that sequence…

I always think that’s maybe the one flaw in a nearly flawless film. For that idea to work, she couldn’t have been very keen to have children. If George had never lived, maybe Mary would have married Sam Wainwright.

Her best “mother” scene is when George comes home and berates the kids after Uncle Billy [Thomas Mitchell] has lost the savings and loan’s money.

Her maternal side comes out because he’s saying such harsh things. When he first comes in, she’s sympathetic and worried, but as he starts to lose it, and breaks things and becomes dangerous, she realizes she has to protect the kids. Stewart plays that so beautifully — the way he just builds and builds and builds. It was astonishing for someone who had previously played such different characters.

What did your mother seek from Capra as a director?

I don’t know for sure. I was born twelve years after “It’s a Wonderful Life” and she was gearing up for TV then and didn’t talk about her film career much. She did say Capra was very demanding but very kind. I think in terms of the work environment he was very professional, in spite of the heaviness that was in the atmosphere. She said he was very open to ideas. If things didn’t seem right and someone had a better suggestion, he went with it. And if he needed time to think about something, he would close the set.

Did she work well with Stewart?

Very well. However, the film was not successful and the reason you never saw her in another movie with him is that he blamed her for its failure, sorry to say.

Wasn’t she going to star opposite him in “The Stratton Story” [1949]?

Yes, but he said no to that. Later, whenever there was a reunion or celebration of "It's a Wonderful Life," she would come as “Mary Bailey.”

Did she see playing Lorene in “From Here to Eternity’ as a chance to break type?

Definitely. She had really become the girl next door during World War II and then it became a bit much. Fred Zinnemann, of course, didn’t want my mother or Frank Sinatra for the movie, though I guess all her auditions were incredible. Thank God she got that role, though it was hard for her to smoke and drink like that.

How strange that Donna Reed should win an Oscar playing a prostitute.

OWEN: Yes, but I think she had things in common with Lorene because Lorene didn’t want to be a prostitute. She wanted a proper life — just like my mother did.

ARTINFO: Did she know how great “It’s a Wonderful Life” is?

OWEN: My mother died in 1986, but by then it was being shown so much at Christmas every year. So, yes, she was happy to see how it was no longer undervalued but greatly appreciated.