Answer:

informer

AnswerCrossword Clue
INFORMERDime dropper
INFORMERCanary
INFORMERMcLaglen's famous role.
INFORMERBetrayer of a sort.
INFORMERMcLaglen's 1935 Oscar film, with "The"
INFORMERTattletale
INFORMERStool pigeon