To identify potential small molecule inhibitors of HES1, Schnell et al. interrogated the Connectivity Map [81], a large collection of genome-wide transcriptional expression data derived from cell lines treated with bioactive small molecules, for compounds with transcriptional signatures that overlapped with that induced by HES1 deletion in NOTCH1-induced T-cell acute lymphoblastic leukaemia (T-ALL) [45]. The gene discussed is HES1; the disease is T-cell acute lymphoblastic leukemia.