The "Castle" star attended the Kusewera benefit party in L.A. on the weekend and rocked a casual ensemble which included an unbuttoned navy blazer over a black v-neck shirt and dark wash trousers.
Looking as ruggedly handsome as usual (seriously, Nathan hasn't changed a bit since his "Firefly" days), the Edmonton, Alta. native let loose a contained smile which had us all swooning.
Not surprisingly, tons of Fillionites tweeted about meeting their man crush.
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