While I didn't watch this movie I'd almost bet the problem was at you local affilliate.
HD programming is received by the local station as an HD feed from the network. When local commercials come on the station must manually flip a switch to replace the network feed with their own upconversion of the local feed. You may notice a slight change in contrast or even color balance when this happens, though it's hard to see on some channels.
In any case, sometimes they forget to flip back to the network HD feed after local commercials, in which case the upconvert of the station's analog signal is shown instead and that upconvert is of the network's non-hd feed once the movie starts again.
This process is automated for the sd network feed vs local origination but not for local originated SD vs network HD feed. I think a very few stations have automation for this but the vast majority do not.
On my local Atlanta HDTV yahoo group, some viewers are on a first name basis with the local affiliate's personnel who handle the flipping of the switch, so when they forget to flip back after the commercials, they get calls aplenty! This is what I call interactive viewing!