Walter was an affluent personality of Maple Heights who owned an airplane hangar in Grimsborough. Walter was wearing a brown tuxedo with a brown bow tie, and he also wore a dark brown aviator cap, covering his gray hair. Walter also had blue eyes.
Walter was found dead after crashing his plane on the way to his wedding party to marry his fiancée, Lola Vallez. They sent his body to Nathan, who confirmed that Walter had died of injuries from the plane crash. Nathan then said that given Walter's expertise in piloting, the killer must have sabotaged his airplane. After inspecting the plane himself, he concluded that the killer knew aeronautics.
The team later found a bottle of de-icing fluid in the victim's plane hangar. Grace analyzed the fluid, only to find that it was a mixture of chemicals that actually made the plane tail freeze quicker rather than prevent its freezing, leading to the plane crash. Grace then concluded that the killer must have had chemistry knowledge to make such a product.
Relationship with suspects
Molly Mocard was heartbroken when Walter broke off his marriage with her, even going so far as to install a security camera in his hangar before the divorce was finalized, so Walter filed a restraining order against her. Lola's brother, Esteban Vallez, disapproved of Walter, saying that he was only after her due to her fame and riches and because he had stopped Lola from financing his contact lens product. Lola had gotten in an argument with Walter after she confronted him regarding the gossip articles on his infidelity, but it was quickly resolved after Walter reassured him that those were false. Meanwhile, Walter accused his mechanic, Yan Gobin, of badly designing the stunt plane. Yan confronted him, telling him that his interest in planes turned to an interest in women, and so Walter threatened to fire him. Walter had also helped Adam Bentley fit in the Maple Heights community, but only to upset the conservative families who would disapprove of Adam's unglamorous background.
Killer and motives
The killer turned out to be Esteban.
Esteban admitted that Lola had stopped giving him money after Walter had convinced her to stop giving him money. Wanting the riches, Esteban mixed a few chemicals to make a few de-icing fluid in order to sabotage Walter's stunt at the start of the wedding. Judge Hall sentenced him to 20 years in jail.
- One Wedding and a Funeral (Case #47 of Grimsborough)
- It All Ends Here (Case #51 of Grimsborough; mentioned)