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Minority Report (2002) More at IMDb Pro »

"First Movement" from "Symphony No.7 (in the past also No.8) in B Minor, D.759 (Unfinished)" (1822) Written by Franz Schubert Conducted by Carlos Kleiber Performed by Die Wiener Philharmoniker (as Wiener Philharmoniker) Courtesy of Deutsche Grammophon GmbH. Hamburg Under license from Universal Music Enterprises.

It's assumed, although the film doesn't explain, that the Temple uses different security than the system we see around the city. Clearly Anderton would be an expert on the Temple and the ways to bypass the security, so he was able to gain entry. It's also possible that there was a human error made in terms of assuming that Anderton would be caught before getting to the Temple, so his access wasn't cancelled. (SPOILER WARNING!) Also, since Lamar is the Director of PreCrime, he could have made sure Anderton still had security clearance, since he was framing John and might have deduced that Anderton would try to break in to get at the precogs.

The music that is played on the organ is "Jesu, Joy of Man's Desiring" composed by Johann Sebastian Bach, from his cantata "Herz und Mund und Tat und Leben", BWV 147.

She is singing a Swedish childrens song about litte frogs (Smaa grodorna). How funny they are with no tails (ej svansar) nor ears (oeron). I can´t see how this has got anything to do with the plot, seems to be more like a practical joke from the actors. Peter Stormare and the nurse speaks a little swedish as well.