In Shakespeare's play, The Winter's Tale, one of the key character is Leontes, king of Sicilia. He is married to Hermione, and it seems their love is loyal and reciprocated. He is also great a great friend, since childhood, with Polixenes, king of Bohemia.
However, in the beginning of the first act, Leontes is going to become unnaturally and quickly blinded by jealousy, thinking that Hermione is making him a cuckhold with Polixenes. This jealousy will become so overwhelmingly important that Polixenes will be obliged to flee from Sicilia, and Polixenes will send Hermione to jail.
The great friendship linking Polixenes and Leontes is introduced to the audience in the beginning of the play by Camillo and Archidamus, respectively lords of Sicilia and Bohemia: "They were trained together in their childhoods" and "rooted between them such an affection" (Act I Scene I).
However, they are already some hints given to the audience that an event is going to trouble this everlasting friendship. The first one (Act I Scene I) is "affection which cannot choose but branch now". Indeed, this has a double meaning, saying that their affection can either grow like a tree but also separate. Another is "there is not in the world either malice or matter to alter it". If there is not something in the outside world something to trouble their friendship, then maybe something coming from inside themselves will, and indeed does.
Act I Scene II sees the entry of all the main characters who will be the most affected by Leontes' jealousy: Hermione, Polixenes, Mamillius (as he is their first son), Camillo (as he will have to flee with Polixenes) and Leontes himself.
The first words of the scene, pronounced by Polixenes are : "Nine changes of the wat'ry star hat been … since we have left our throne". He is saying that he has left his kingdom for nine months. This is a subtle coincidence brought up by Shakespeare as it exactly the period of pregnancy. As well as being another hint...