From Arkham Horror Wiki
Thomas Olney is an ally. He first appears in the Kingsport Horror expansion. He can be gained through an encounter at The Rope and Anchor.
You are Blessed when Thomas Olney joins you.
Olney appears in the story The Strange High House in the Mist (1926), written by H.P. Lovecraft, as a philosopher who visits the strange house while on a visit to Kingsport.