. >> both: hey, bada, bada, bada bada, swing bada! >> never was a cub fan. never will be.chicago white sox weren't playing day games, so i had to shoot at wrigley field, which is a very nice ball park, but wrong team. >> narrator: from wrigley, they took a surprise turn for a shot of culture. >> it originally said they'd go to the museum of science and industry. and then we went and scouted the art institute, and then john just said, "oh, if we can shoot here, i want to shoot here." >> it was a thrill to be with those paintings for a whole day in an empty room. that was a great pleasure. >> this was going to be the most paintings ever in a movie that we were gonna see. >> it took us a while to get permission to shoot there and a lot of restrictions on lighting and the paintings. these are classic works of art. the painting that cameron was looking at was seurat. he was a pointillist painter. painted with the dots. but john saw it, and that wasn't written in the script. he saw that and go, "oh. i can say something about cameron, about how locked he is into his own life." >>