- You may be looking for the Past Doctor Adventures novel.
"The Hollow Men" was a poem by T.S. Eliot.
Richard Lazarus quoted the poem to Tish Jones, "Between the idea, and the reality, between the motion, and the act...", with the Tenth Doctor finishing "...falls the shadow". After Lazarus' death, the Doctor told Martha Jones that Eliot was right, quoting, "This is the way the world ends, not with a bang but a whimper". (TV: The Lazarus Experiment)