*rubs temples* Okay, this is a really sticky question I have here. Please read the sceanrio I give and the question I ask, and then please give a nice clear answer.

Scenario:

My side: 1 mon

Opp's Side : 1 mon

Opp's Turn: Plays Soul Exchange, planning to sacrafice my mon and his for Dark Magician.
I counter with Michizure, destroy his monster.

Question:
What exactly would happen?

Please help clear up the effect of my counter for me.

You cannot activate Michizure, because the last thing that happened was Dark Magician being summoned to the field, not your monster going to the graveyard.

darkman is correct.

michizure has activation requirement that the last action was your monster going to the graveyard, and since you cannot inturrupt a summon until it is completed the last action was now a summon, and michizure's timming is incorrect and can't be activated.