The traditional vision that international courts and tribunals do ‘good’ or create a better world through law is increasingly under question. International criminal justice started largely as a ‘faith’-based project, but is increasingly criticized in light of its actual record and impact. This essay examines this journey and, in particular, the role of ‘faith’ and ‘fact’ in the treatment and assessment of international criminal courts, through four core themes (‘effectiveness’, ‘fairness’, ‘fact-finding’, and legacy’) addressed in André Gide's version of the parable of The Return of the Prodigal Son. It argues that, in its ‘homecoming’, international criminal justice would benefit from a greater degree of realism by openly accepting its limitations and embracing its expressivist function. It cautions at the same time against exclusively quantitative understandings of impact, arguing that the power of international courts and tribunals lies not so much in their quantitative record as in their role in setting a moral or legal example or shaping discourse. It concludes that a better match between ‘idealism’ and ‘realism’ requires greater attention to the interplay between ‘international’, ‘domestic’, and ‘local’ responses to conflict, as well as recognition of their legitimate differences.