Heidi is a UFO researcher and author best known for her work regarding Shadow People and Hat Man. Terms she describes for the unusual dark figures people see in their rooms at night.
Check out Heidi's many books
https://www.amazon.co.uk/stores/Heidi-Hollis/author/B002CI0A4O?ref=dbs_a_mng_rwt_scns_share&isDramIntegrated=true&shoppingPortalEnabled=true
