i was kind of thrown when the actual actors started talking about their roles in the middle of the movie. it was daring and original tho. Also, so was Andreas the name of max von sydow's character AND anna's dead husband? Not to sound dim but these were points i was curious about
This is called "deconstruction" I believe. I think Bergman was trying to express his love for good actors and acting. The film has some amazing performances and I believe a lot of the dialogue was improvised. The interviews with the actors give us an idea of how the actors portray their characters, kind of blurring the line between the actors themselves and the characters they are playing.
A correction about improvisation: None of the "interview" scenes were improvised. According to various interviews with Bergman and the actors in the film, the only scene in the film where improvisation was encouraged was the dinner party with the four characters sitting around the table. In the original story that Bergman wrote prior to filming (which can be found in the book "Four Stories by Ingmar Bergman"), four brief character monologues can be found, expressing the very themes which the "actors" discuss in their fictional interviews.
"I'm sorry to say that those [interviews with the actors] are very unsuccessful. I just wanted to have a break in the film and to let the actors express themselves. Bibi Andersson and Liv Ullmann improvised their interviews, but Max von Sydow and Erland Josephson had no idea what to say, so they said what I told them to. This led to two different films, and I no longer understand why I left the whole batch in, because I always realized that they wouldn't work. But I like coups de theatre, things that make people wake up and rejoin the film. This time, however, it wasn't successful."
— Ingmar Bergman, interview with Charles Thomas Samuels, 1971