Arlo originally lived on Thursday Island. When he was young the island was struck by a great wave, destroying his home and leaving him as the last living member of his family. He has a great affinity with the local mutant birds known as Angels. After the wave hit he was brought up by the Angels, and as a result when he was taken back to Mayda he was very reclusive and had almost forgotten how to speak. When he arrived back in Mayda he was taken in by a shipwright named Blaizey and fell in love with his daughter Thirza, who showed a keen interest in the Angels and may have felt the same way for him. Thirza eventually turned Arlo turned him down for a rich and powerful man named Jago Belkin, though Arlo continued to love her through to his adult years.
A Web of Air
In the main part of the story Arlo met Fever Crumb when she visited his house on the Casas Elevado to find out more about his passion for flying. He wass very hostile to her at first and even pointed a gun at her; later on he became a lot calmer towards her and showed her how he planned to work his aeroplane. After Fever angered Arlo by mentioning Edgar Saraband, she was chucked out of his household and he wouldn't even open the gate to her. He sent Weasel (one of his Angel friends) to spy on her and summoned the Aranha from the secret pool in his garden. At the end of A Web of Air, Arlo sailed off from Mayda into the Atlantic Ocean in his boat, The Jenny Haniver, towards the lost continent of America. After this he is not seen again in the series and his fate remains unknown.
Arlo is described as being in his early twenties and having "dark, tousled and much too long" hair which covers his eyes which are green. He has freckles and a "sallow" complexion.