Overall, in this study, we reveal that Id2 restrains immune evasion by disrupting the formation of the Tcf3-Tal1 transcriptional regulatory complex and its recruitment of the histone lysine demethylase LSD1, thereby increasing the abundance of the permissive H3K4me2 mark during hierarchical CD8+ T-cell exhaustion in cancer. The gene discussed is ID2; the disease is cancer.