Telemachus  returns to Ithaca and Odysseus  reveals  himself to his son. 

They then  plan  to kill the  suitors. 

The next day, there is a  contest  to string  Odysseus's bow 

and send an  arrow  through 12  axes. 

Out of all the suitors,  Odysseus is the  only one  who can do it. 

Then, as  Antinous,  the  leader  of the suitors, is  taking  a drink, 

Odysseus  shoots  an  arrow  at him  and kills  him. 

Odysseus and Telemachus  battle  with all the  suitors  and  kill  them.