The way Arlo discovered his power was in 1939 when he was on a mission to discover the secret recipe of Pepsi. He had 21 minutes to get the recipe back to his boss
Suddenly the owner of Pepsi came into the room, however, Arlo has transformed into water just before the owner could suspect anything. He realized he always transformed into water after 21 minutes of his mission because of how mentally unstable he was in public. He could transform back into human form but he need to stay still for 2 minutes.
After discovering his power, he vowed to use his power for the greater good as he was living in a time of chaos and turmoil.
Arlos latest mission was to investigate where Henrietta Fore, executive director of UNICEF was hiding money earned from charity events.
As dawn has struck, Arlo got ready to drive out to New York city to see where Mrs Fore was heading. He strived to arrive there before 6:30 as that was the time she usually left the UNICEF headquarters.
He got there just in time! He inwardly did a happy dance, got into his car, and followed her.