I watch him take his notebook and a marker pen from his bag. As he zips the compartment back up I see the tip of our large, serrated kitchen knife, the one that went missing last night.

Zach was nineteen when Tanya discovered him rerouting the wires of their landline, sure that the phone was bugged, that his friends were Mafia, that the helicopters swirling above were deployed by spies, that he couldn’t trust anyone – her included.

That moment upturned and unmoored everything. It would strand them both in a profound and terrifying isolation the way that perhaps only a psychotic break – or loving someone who is experiencing one – can.

Zig-Zag Boy is a journey along the tough frontiers of love and madness. As Tanya fights for answers and understanding – coming up against broken healthcare systems in the UK and the US – she is forced to question whether there were warning signs she missed, whether Zach will be able to have a normal life, and what ‘normal’ really means.