Michael Hogan, of Battlestar Galactica fame, guest stars on the episode "Patriot." He portrays Colonel Slade.
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Alan Ritchson is seen in this shot from the episode "Patriot." The character makes a major comeback on the final season of Smallville.
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Alan Ritchson returns to Smallville on the episode "Patriot." He reprises the iconic role of Aquaman.
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Smallville Season 10 Episode 9 Quotes

It's not the first time he's gone Che Guevara just to protect the big blue, and lets face it, now that the VRA has all of us looking over our shoulders, team communication has gone from full bars to no signal.

Oliver (about AC)

It's time we took these heroes under our control and proved who's really fighting for truth, justice and the American way.

Slade