"Said the actress to the bishop" is an informal (and usually vulgar) exclamation, said for humour in the form of a punch line after an inadvertent double entendre. The equivalent phrase in North America is "that's what she said".
History and background
"Said the actress to the bishop"
The term, or its variant "as the actress said to the bishop", may have been used as far back as Edwardian times, and is apparently British in origin.
The phrase is frequently used by the fictional character Simon Templar (alias "The Saint") in a long-running series of mystery books by Leslie Charteris. Th...