Factual error: The building shown between the stated times is located in Japan instead of the US/Washington DC as suggested by the actions in the scene. This is proven by by the Chinese characters In the Dark-gray concrete wall in the lower left side of the frame, as well as the red and blue colored circular road signs in the lower far right of the frame which are not in use in the US but in this combination unique to Japan. The street furniture, such as the road markings, the vegetation and the buildings also resemble Tokyo. (00:06:55)
Factual error: At the very beginning of the episode, during Agent Wells' escape in the blue van, there is a very tall skyscraper in one shot. There aren't large skyscrapers like that in DC. Also, when she crashes the van into the Tidal Basin, where did all of the cherry trees that surround it disappear to?
Factual error: In the opening scene, Abe Leonard meets with a terrorist leader in what is supposed to be Iraq. However, during their conversation, their breath can be seen, even though Iraq has a hot, dry climate. Even at night, the temperature rarely drops low enough for your breath to condensate, let alone in an urban area during daytime.
Answer: The line of succession is VP, Speaker, President Pro Tempore, then the Cabinet Secretaries in the order the department was created. If none is qualified, then the Chief Justice or senior member if no Chief or Chief is ineligible or declines, acts as POTUS until either the House chooses a new Speaker or the Senate chooses a new Pro Tempore, whichever is first.