Three Act Structure

Three Act Structure is a basic structure purely used for the organisation of films, so the structure is easily followed by viewers so they are much more engaged within the film.

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Beginning

The Beginning can be an opportunity to establish the characters in the film. With the film Taken, you develop an understanding that Liam Neeson will be the Protagonist in the film, as he takes lead of the film in certain situations, partially being the main focus, based on his particular set of skills he possesses. 

As well as being a way of introducing characters into the film, it's an indication of what the story is going to be about. With Liam Neeson's daughter going to paris, this is establishing where the plot is going to be based. The fear of his daughters safety, due to his past experiences of being a preventer, gives you an inclination that things might not go so smoothly in Paris and his fears may become his reality.  

Middle

This is where a crisis is revealed, where actions must be taken, in order to attempt to overcome an obstacle or resolve a situation. When the Father realises his daughter is about to be kidnapped in Paris, he goes to Paris relying on his particular set of skills to track down the corrupt gang who abduct women, to rescue his daughter from prostitution. During the middle act of the film, Liam Neeson does whatever it take to get closer to finding his daughter, hunting down and killing whoever gets in his way.

End 

This act is the stage of resolving the crisis or finding a solution. In Taken, after hunting down the ruthless gang and killing every single one who puts his daughter at risk, he eventually finds her and rescues his daughter, finally being in a state of equilibrium. In some endings not everything is revealed, which is referred to as a cliffhanger. This is purposely done to keep you in suspense, so your in questions about the next film, that will eventually reveal what happens in the next part of the story answering all your questions.