There is considerable speculation that prisons are a breeding ground for radicalization. These concerns take on added significance in the era of mass incarceration in the United States, where 1.5 million people are held in state or federal prisons and around 600,000 people are released from prison annually. Prior research relies primarily on the speculation of prison officials, media representations, and/or cross-sectional designs to understand the imprisonment-extremism nexus. We develop a tripartite theoretical model to examine continuity and change in activism and radicalism intentions upon leaving prison. We test these models using data from a large probability sample of prisoners ( N = 802) in Texas interviewed in the week preceding their release from prison and then reinterviewed 10 months later using a validated scale of activism and radicalism intentions. We arrive at three primary conclusions. First, levels of activism decline upon reentry to the community ( d = -0.30, p < .01), while levels of radicalism largely remain unchanged ( d = -0.08, p = .28). What is learned and practiced in prison appears to quickly lose its vitality on the street. Second, salient groups and organizations fell in importance after leaving prison, including country, race/ethnicity, and religion, suggesting former prisoners are occupied by other endeavors. Finally, while we identify few correlates of changes in extremist intentions, higher levels of legal cynicism in prison were associated with increases in both activism and radicalism intentions after release from prison. Efforts designed to improve legal orientations could lessen intentions to support non-violent and violent extremist actions. These results point to an imprisonment-extremism nexus that is diminished largely by the realities of prisoner reentry.