It turns out that Lucas was being so accommodating to his cellmate because he was hoping to get some valuable information from him. We learn that Lucas made a deal with the FBI that gets him out of prison and into Witness Protection, where hell be given a second chance. Its a turn of good fortune for a character who sees very little of that. Lucas has had a rough time thus far on the show, not least of all losing Zoe, but this is the first time we see things start to work in his favor. He has a nice house, a decent job in car detailing, and a new identity. He has a chance put all the dark moments behind him and move on. Or it gives him one last chance at taking down Frank Underwood once and for all.