We knew Alex and his dad shared a rocky history on Grey’s Anatomy, but we’re about to learn just how deep their conflict runs.

In this Thursday’s episode (9/8c, ABC,) Alex confesses to new squeeze Jo the real reason he can’t bear to go near his hospitalized father (a perfectly cast James Remar).

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“The last time I saw his face I was punching him so hard I could’ve killed him,” he shares. “I’m just afraid I’ll pick up where I left off.”

Also in the following clip, we get the scoop on the origin of Alex’s last name and we see where he gets his ladies-man swagger from.