Factual error: When in Amsterdam, there are a number of mistakes with Hanna's car. First off, it's a brand new model, but it has a numberplate from a series six years ago. Second, that numberplate is a flat sticker, while Dutch numberplates are made with very thick plastic letters. Third, the registration is 87-UYM-3, which wouldn't be used, given that Dutch numberplates don't use vowels.
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: 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.
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: FBI Agent Hannah Wells pulls up to the house of the First Lady's mother driving a unmarked police vehicle with government license plates. The license plate is I410918, which is a Department of Interior plated vehicle. The FBI wouldn't be driving a Department of Interior vehicle as the FBI is in the Department of Justice. A Justice plate would have a J and a FBI agent vehicle would have a regular license plate. (00:14:00)
Factual error: The dirty bomb went off at the Brandt Metro station. There is no station with that name.
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.