By all accounts, Bartlett was a quiet and studious man who mostly kept to himself. He was courteous, kind, and slightly nervous around other people. But beneath this meek and unassuming attitude lurked the heart and soul of a pervert. Bartlett managed to keep this side of himself unknown to everyone, which was perhaps the catalyst for his mysterious disappearance.
The exact date that Bartlett arrived in Hollywood is unknown, as he never kept a diary or journal. But it was before the Battle of Los Angeles (68 BBO), as one of his recovered sketchbooks contains several drawings of the event. He may have been called to Hollywood by Whit Jolley himself, as Bartlett worked as principle character design on numerous Jolley films. It was during this tenure that his reputation as an animator of the cute was established.
As time progressed, Bartlett became more and more of a recluse. He was rarely seen in public, and sequestered himself inside his apartment in Sunset Slums for months at a time. He was first reported missing in 31 AH. Much like his arrival, the exact date of his disappearance is unknown, as it was only discovered during a delivery that could not be signed for: ten crates of canned beans and an equal quantity of whiskey.