Narrative viewpoint in a film is important as it shapes the audience's knowledge, opinions and emotions, just like in a story. A film that's told well will display the film in an appropriate way, for example a moving story like 'My Sister's Keeper' would not be as effective in a third person PoV as the audience would not be able to connect as emotionally to the character. However, in film it can be harder to distinguish a PoV at times, especially in times when the fourth wall is broken, shifting it to a second person PoV.

First Person Pov is argueably the most common PoV used in film, due to the way it helps the audience connect with the character(s). However this stance is not always done through the shot itself. A voiceover from the character, camera focus on them, intimate scenes and only seeing their side of the story helps to define this stance. Films like Kickass, Elf, Shrek and Tangled show this PoV  to tell the story. However, in the world of gaming, first person PoV is more successful as it is a way to submerge the player as they are the ones who make decisions that affect the outcome of the game, e.g. The Stanley Parable, Minecraft and Call of Duty.

Second person PoV is much harder to pull of in film, as it's harder to direct something at the audience in that way. Breaking the fourth wall is probably the only way a second person (the audience) is addressed. Breaking the fourth wall is often used as a comedic aspect, as to include the audience in a joke, but it can also be used in thriller/horror to scare the audience or make them uneasy and to highlight someone's malevolence. 

Third person PoV is often used in alliance with first person PoV, so that although the audience is following the plight of a character, there is still some distancing. This combination is used in a majority of films, but for a film to be more dominantly in this third person stance, a narrator outside the film is used, more characters are included in the story line and the shots won't be as close, nor will there be as many intimate scenes.

For our film trailer, a first person/third person combo would be best. Many thrillers use this viewpoint, mixing together intimate scenes and multiple storylines that converge to create a tense and atmospheric film with a sense of impending doom. The intimate scenes help for the viewer to grow close to the character and fear for them, thus helping add to the feeling of the thriller.