Caleb Taylor was a worker at the Richland Chemical Plant and widower with two sons, Benjamin and Elias, at the time of the First Invasion.
His family was in turmoil when Caleb constantly nagged Elias about becoming more worthwhile than a black market dealer. Ben was a benevolent doctor that Caleb was very proud of him, often using him as an example while lecturing Elias. Elias was quite resentful of both Ben's success and his father's constant nagging about his lifestyle of a thief and gang member.
Upon the first arrival of Visitor technicians at the Richland plant, Caleb is openly xenophobic, thinking the aliens are there to put him out of work. When he meets a Visitor technician, Willie, Caleb glowers at him in contempt. Later, Caleb was injured in an accident that released a large amount of nitrogen gas, freezing everything in a chemical chamber he'd been working inside. When Caleb's panicked supervisor believes there's no hope of getting Caleb out, he's rescued by Willie. Caleb expresses his deep gratitude to Willie after he returns to work, even sharing a friendly moment where he teaches his new friend how to do a "gimme five" gesture.
When Benjamin joined the Resistance and was killed by the Visitors, Caleb and Elias both become active members of the Resistance to avenge his death. (V: The Original Miniseries) It takes some time for their friendship to build again; Caleb's hatred of the Visitors becomes apparent again at his son Ben's funeral. Willie offers his condolences and Caleb yells for him to go away. The incident seems to be forgotten later and Caleb begins to trust Willie again.
While a Resistance member, Caleb offered many suggestions and advice on strategies for the group, his life experience contributing to his wizened nature. As the Resistance continued to operate and grow in number, Caleb and Elias' new relationship proved to be more than useful with Caleb guiding his son and often learning from Elias' own experiences.
When capturing Brian, though Ham desired to kill Daniel himself for killing Ruby, Caleb had a better plan: he framed the traitor for the capture of Brian instead, which gave Steven the motivation to have Daniel be tortured, killed and eaten.
When Willie was captured for research into the Visitors biology several months later, Caleb vouched for his protection and freedom as he considered him more trustworthy than most Visitors. During the discussion for the final attack on the Visitors with the Red Dust toxin, Caleb feared nuclear annihilation and voted against it, while Elias supported it. Caleb tells his son he's proud of the stance he took and Elias' new respect for humanity and the need to save the Earth.
Caleb accompanies Mike Donovan, Juliet Parrish, Sancho Gomez, Harmony Moore, Willie and many others onto the Visitor Mothership over Los Angeles. Caleb provided much needed muscle to saturate the ship with the red dust, even taking up the heavy hose to kill a shock trooper unit sent to kill them. His unit's efforts are successful, allowing the ship to be captured by the Resistance and Earth be saved from destruction. (V: The Final Battle)
Whether he is still alive during the Second Invasion or he lived to see his second son, Elias, die in combat, is unknown. (V: The Series)