Once you've outlined the five main plot points of your screenplay, you know how your hero is locked into the dramatic situation, you know if your character reaches a high or low point by the midpoint and main culmination, and you know how your story ends. After that, it's really just a matter of creating believable conflicts for your character, and that means obstacles.
The most important thing to remember is that confict is bliss; it truly is your best friend. And your audience expects it. Right when the audience thinks it can't get worse for your character(s), it gets worse; and when there is absolutely no way the situation can get more severe, it does; and finally, when there is no possibility things can deteriorate even more, it rains. It always rains.
If you want to write movies, then you better understand that a central character cannot exist without conflict, so it's your job to make sure you have enough obstacles (internal and external) for your character to face.
And when you do this, really go for it: Attack! Go for the jugular! Hit your main character at his or her weakest spots, because when you corner your characters, and I mean really squeeze them, they will show things about themselves that they don't want to reveal. And those are the scenes we want to see.
Take Braveheart (1995). You don't have to love the movie to appreciate the power of one scene where Robert the Bruce betrays William Wallace and everything Wallace stands for. As the Scots are losing the Battle of Falkirk against the larger English army led by King Edward Longshanks, Wallace breaks ranks and charges toward Langshanks to kill him personally, but he is intercepted by one of the king's hooded lancers and knocked from his horse. When the lancer dismounts to examine the fallen Wallace, Wallace gains the upper hand and is set to kill him, but upon taking his helmet off, Wallace discovers his opponent is Robert the Bruce, the chief contender for the Scottish crown and the very man Wallace put all his faith in Scotland behind. Even though Robert the Bruce doesn't kill Wallace physically, he has broken Wallace's spirit, and it will take everything for Wallace to regain faith in the nobility of his country.
The previous scene is an example of literally squeezing the life out of a character: Wallace has lost the battle, been shot in the chest by long-bowmen's arrow, betrayed by two other Scottish nobles (Lochlan and Mornay), and his spirit crushed by Robert the Bruce, the one noble Wallace himself said he would follow.