Peter Bennett is an art director who has worked on the show since 1999.
He is best known for being one of the main background painters in the series, throughout 182 episodes total between 1999 and 2014, as well as being the hand actor for the character Hans, (although his voice is provided by Tom Kenny.) Very little is known about him, despite being a crew member on the show since the beginning of season 1.
Along with this, he is also known for being one of the main art directors for 161 episodes between 2005 and 2021, some including "Hooky," "Wet Painters," and "Squeaky Boots," among many others. His acrylic paintings are immediately recognizable for long-time viewers of the show; they are mainly used for backgrounds, promotional materials, and especially detailed close-up shots.