Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This is a bio pic of Alexander the Great. Leonard Maltin calls it the first Oliver Stone movie that can be described as boring. True, Alexander is not great, but I would never call a movie boring in which Angelina Jolie plays with snakes. And there are plenty of other serpentine appearances, for anyone crazy enough to be into, that which can help pass the time between all the grand speeches and bload-drenched battles.
Jolie plays Alexander the Great's mother, Queen Olympias, who some called a sorceress. I think the snakes are supposed to show us of her deep connections with the earth and witchcraft and all that mythical nonsense of sorcerers. And it seems that some ancient authors thought that Olympias was "visited by" the god Zeus who appeared to her in the form of a serpent and fathered Alexander. She tells Alexander a few times that Zeus is his father, not Philip, but he has his doubts. Many of the times we see Olympias she is hanging around her room with wild snakey hair that looks like it needs some serious brushing (but probably took a stylist three hours to get that way) and she is either holding a snake or there are snakes wrapped around her legs or crawling on her or around her on the floor. Apparently back in B.C. you didn't need a terrarium and heating elements to provide a suitable habitat for snakes because Olympias just keeps a bunch of them in a big basket. We see her teaching Alexander about snakes as she tells him they are his friends and teaches him to never hesitate. She also wears a snake bracelet, she has a snake tattoo on her lower back down her thigh, and her bedcovers and curtains are embroidered with snakes. In an early scene her husband King Philip is drunk and trying to rape her and she fights back until Philip sees the young Alexander hiding under the covers which makes him so angry that he knocks over the basket full of snakes and accuses her of keeping him like one of her snakes.
Later Philip is teaching tween Alexander about the myths connected to the drawings in a dark cave. He tells him of Oedipus who cut out his eyes after realizing that he'd married his mother and of Medea who killed her own children after Jason left her for a younger woman. This freaks out Alexander who says his mother would never hurt him. Then Philip tells him its not easy to escape our mothers and he should beware of women because they are far more dangerous than men. Then we see a pair of snakes crawling on the ground to remind us of Olympias, just in case we're too stupid to do that on our own. The movie flashes back to these cave images throughout the movie to remind us of the power of these myths and how they continue to affect Alexander.
When Alexander decides to marry a "hill girl" in distant Asia (Rosario Dawson) instead of returning home to marry a Macedonian woman, nobody understands why, but we do. She wears a snake bracelet and has a snake painted along her dorsolateral regions on her wedding night, which ends up in a naked knife fight because, in case you forgot, this is an Oliver Stone movie. She also has the same hot temper and annoying accent as Olympias.
When Alexander's army is in India we see another snake dangling from some vines where men are working. It bites one of them on the neck. Alexander calls for a "snake healer" and we see a guy with a snake painted on his face hovering over him, but it doesn't look like he'll survive.
Alexander is depressed in bed and we see a large albino snake on his lap which means he must be thinking of mommy dearest.
At a party where Alexander is wearing a lion's head on his head he starts to drink out of his huge bowl of wine when he sees Olympias with a Medusa head full of snakes. He makes a toast "to the myths." Unfortunately, he forgot to pay attention to the parts in myths where kings drank poisoned wine and he keels over to die later, after the requisite montage of scenes from his life, which include his mother holding a snake and a shield with a Medusa on it.
Several times in the movie we see Alexander watching eagles in the sky and there are some references to the eagle that eats Prometheus' liver every day. When Alexander dies he sees an eagle flying towards him that helps to choose his successor. Right after that Olympias looks out her window and sees an eagle drop the snake it was carrying, a message to her that Alexander is dead.
The eagle and the snake are fake, and a few fake snakes fall out of Olympias' basket, but the other snakes are real. We see some normal and albino Corn Snakes, and some other species of albino snake, and the snake around Angelina Jolie's shoulders is a Ball Python.