Hmm… so you have already decided the title, cast, the plot and even the release date of that film.
So, perhaps the reason you asked the question in the first place is either because you want to see if that film will be to our liking OR because you are planning on another film.
If it is the latter (I hope it is) then the following might be helpful:
1. The title should be something catchy and the film poster, attractive, the trailer should be superb and tempting.
2. All-back-to-normal and satisfactory ending. There should be at least two survivors.
3. Main character(s) should not die or, at least, should live.
4.There should be wonderful, lovable and satisfactory twist(s).
5.Excellent but less known actors. All actors should be really good at acting.Special recommendation – James Marsters.
6.If a mystery movie, then less number of characters and limited area might make it more thrilling.
7.Complex themes or plots that are understandable to only professionals, can be unsuccessful.
8.Words that mean something when read one way and quite another thing the other way, might help. Eg- WOW and MOM
9.Cool or eccentric or smart detectives as characters in a mystery
10.Complex, eccentric, smart, in-depth characters.
11. The plot should be fast and should NEVER drag on and on.
12.Smart, witty, appropriate dialogues.
13.Quite modern situations. Don’t think of ancient plots.
14.Sparks of romance between some characters.
15.Characters who remain cool about everything that happens are either the actual villains or people with real good insight. This can be used for deception.
16.The time of day can be an effective thriller. Like 12:00 midnight or the use of the number 666.
17.It would be a good idea not to reveal the villain till the end, so that audience might think “I never thought of that”.
18.If the villain continues playing indestructible, it will be boring (or perhaps even scary)
19.Death of ‘some’ (minor) characters. Too many deaths make it lame. If there are no survivors or just one main survivor, it would be lonely…
20.Following the wrong clues or trails for some time before the mistake is realised.
21.Create a situation of dramatic irony where the audience yells at the character to do something or not to do something, while the character is unaware of the consequences. Or when the villain is known by the audience but not the hero.
22.Bad guy turning good or vice versa.
23.Something to have the attention of the audience and keep them spell-bound, so that they really jump off the seats when something scary happens. Like evil, cold, high pitched laugh in the middle when the audience is so absorbed…
24.Electricity failure or, best, malfunctioning (esp. light).
25.Uncertainty in the matters of trust, right decision, no-other-choice-but-this, etc.
26.Effective use of lightning, moonlight, footsteps, a sudden movement or sound, shadows, background music etc to intensify the crisis. Eg – revealing a scary face at the flash of lightning and/or rumble of thunder; hearing footsteps come near when a character is most scared, etc.
27.Things that do not connect till the middle of the movie, effective tying of loose ends, etc.
28.As much believable reality as possible. Like the police actually turning up.
29.Do not focus only on one character, even if it is the main one.
30.Having the audience think at first someone is a villain, then all the evidence points out that he isn’t (the audience believes it, too) and then finally it turns out that it truly is him. This can be an effective deception.
31.So many clues… uncertain where to start… time is short… dangers rise…
In addition, you can refer:
1)Harry Potter (Books NOT movies)
2)House of wax (film)
3)Mummy & Mummy returns (films)
4)Evil Dead I and II (films)
5)Agatha Christie books & films
6)Mind hunters (film)
7)Saw I, II and III (films)
8)Anaconda I (film)
9)And there were none AKA Ten little Indians ( book and film)
10) Psycho I, II, III and IV (films)
People really are at the edge of the seat when their favourite actor or character is in mortal peril or is about to be attacked from behind, when evil stalks someone, etc…
What makes us really see a movie again and again:
1)Excellent acting of the actors.
2)Lovable characters.
3)Appropriate witty and cunning actions or dialogues or laughs or even expressions of villains.
4)The stunning discoveries. The end. The final fight. Etc
In horror films the following greatly matter:
1)Supernatural scary beings or situations.
2)Death – The number of deaths AND the types of death
3)Marvellous portrayal of villains and Super-villains.
4)Characters matter far more than actors.
Hope I have been helpful.