18a) Vent anger on school's Dickensian character (7)p---n-p (parsnip????)
20a) Conflict not required to see off a group of Nazis (6)n-e-l-
24a) Seizure by police to get the job done (3,3,4)-i-/t-e/----
26a)Lower number follows unspecified one (6)n-----