THE TRIAL AND DEATH OF SOCRATES is a compilation four dialogues: the "Euthyphro," the "Apology," "Crito," and the "Phaedo". As the title clearly states, these four dialogues convey the story - and philosophical debate - that surrounded Socates' trial and death. In these dialogues we find Socrates defending the righteousness of his actions and views, and tearing away at his prosecutors with the skill of expert lawyer. His only weapon being the truth.
In spite of, or perhaps because these four dialogues were written while Plato was still a middle-aged man (as opposed to the "Republic" and the "Laws," which are thought to be his more formulated philosophical expressions), they absolutely sizzle. The text bleeds with life, and so-called Socratic method of endless penetrating questions is here exemplified in the most dire of occasions - Socrates defense against the State of Athens.
It is in these dialogues that Plato expresses the core of philosopohy: a committment to truth, beauty and justice, and the the supreme tenent: "The unexamined life is not worth living." That said, if you still yearn for more Plato after reading these dialogues, grab a copy of Allan Bloom's translation of THE REPUBLIC. It is currently the best English translation available, and you will still be saving [money] over an edition of Plato's complete works.