I expected to hear back from them but I never heard a 'whisper'. [=I never heard from them again]
“I've had more than I can stand,” she complained in a 'stage whisper'.
I couldn't hear what they were saying because they were 'whispering'.
(..) For years it poisoned his mind. And in the gloom of Gollum's cave,it waited. Darkness crept back into the forests of the world. Rumor grew of a shadow in the East... ... whispers of a nameless fear. And the Ring of Power perceived... ...its time had now come. It abandoned Gollum. (..)2001 The Lord of the Rings: The Fellowship of the Ring