Abstract: Show trial psychology presents a problem that neither coercion nor performance adequately resolves: how did accused party members, subjected to no physical torture in many documented cases, produce confessions whose psychological markers were indistinguishable from genuine conviction? At its centre lies manufactured sincerity: the condition in which a thought reform process produces authentic belief in the mind it reconstructs, rather than mere compliance from a resistant one. Drawing on the 1952 Slánský trial and the diagnostically instructive partial failure of Traicho Kostov in 1949, the analysis traces how graduated commitment mechanisms, systematically applied within total institutions, progressively eliminate the cognitive exits through which resistance becomes available. The show trial is not an interrogation chamber but the public performance of an architecture already completed in private. The mechanism's operating conditions — identity constitution through institutional categories, exit closure, and escalating compliance — are not historically confined.