Marco Lesa
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Marco Lesa is a Returner who hides away on the Phaeton 5.
His daughter, Jenny, was apparently aboard this ship and have been reunited. He protects her from serious injury after he is critically injured in an Earth Protectorate bombing.
Commander Adama asks him to help in a "cause" to find Earth. In reality, his "help" involves tagging each Returner with a small explosive device in the event that they behave as humanoid Cylons) (Battlestar Galactica 6).