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Tear Jerker: Quantum Of Solace
Mathis' death scene was genuinely heartrending... until the Mood Whiplash hits.
The scene with the Bolivians crowding around a dripping tap attached to an empty tank... and seeing the last drop drip out.
Agent Field's death, especially when it is revealed that she was not even a field agent. She was so swept into Bond's world, wanted to do her part, but ended up being killed by enemy agents.