Read the excerpt from Hamlet.

Hamlet: Follow him, friends: we’ll hear a play to-morrow. [Exit POLONIUS, with all the Players but the First.] Dost thou hear me, old friend; can you play the Murder of Gonzago?

First Player: Ay, my lord.

Hamlet: We’ll ha ’t to-morrow night. You could, for a need, study a speech of some dozen or sixteen lines, which I would set down and insert in ’t, could you not?

First Player: Ay, my lord.

To make the First Player a complex character, Shakespeare would need to make him

represent a single idea.
have few emotions.
change over time.
have a simple personality.