A true story based on Harry Hallowes (Brendan Gleeson) who first squatted on the site in 1987 after being evicted from his council flat in Highgate. Hallowes, who died aged 88 in 2016, battled for the legal rights to own the land on which he had built his shelter arguing that he had gained ownership by "adverse possession". Hallowes was eventually awarded 7,000 square feet (650 m2) in title deeds.