Famous musical (6)
(Other definitions for oliver that I've seen before include "Cromwell, for example" , "Dickens boys who asked for more" , "- Goldsmith (She Stoops to Conquer)" , "-- Reed, actor" , "Lionel Bart musical" .)
'famous musical' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for evita that I've seen before include "Musical based on Argentine leader" , "Juan Peron's wife" , "Show" , "Peron musical" , "Well-known musical" .)