Plato is one of the avid followers of Socrates. It is important to note that almost everything we know about Socrates comes from Plato. Plato's writing comes in a form of Dialogue. Almost always Socrates serves as a mouthpiece for Plato's Doctrine, so it is sometimes to difficult to differentiate the original thoughts of Socrates from that of Plato.
I'm not entirely sure how many times the impending death of Socrates was used as background of Dialogues. I'm sure of these works however.
Apology - It is actually a "monologue", it is Socrates' defense of his own trial.
Crito - Socrates was offered a chance of escape, but he declined the offer.
Phaedo - Sorates last word before he drink "hemlock"