Porthos Timeline and Summary

Porthos is distraught because he has nothing to wear to the party at Vaux.
Porthos helps Aramis swap the King of France for a prisoner from the Bastille.
He flees with Aramis to Belle-Isle when the plan fails. He thinks they're on a secret mission for the King.
Aramis finally tells Porthos the truth when they're at Belle-Isle, surrounded by the King's soldiers. Rather than flee, Porthos decides to stick it out with Aramis.
Porthos has a premonition that he will die soon, and writes his will.
Aramis and Porthos attempt to make their escape from a grotto on the island. Porthos kills over a hundred soldiers.
The getaway boat is ready and Porthos is seconds away from safety when his legs give out. He cannot escape from the grotto.
Porthos dies in an explosion and subsequent rock fall.