Who did Macbeth have killed in act 5?

No, Banquo didn't die in Act 5 of the Shakespearean play. Macbeth [c. 1014-August 15, 1057] planned Banquo's death, in Act 3 Scene 1. The murderous plan was carried out in Scene 3. Three murderers waylaid Banquo on his way back to Macbeth's post-coronation banquet. They left him, with his throat slit, in the park near the royal palace at Forres.