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Location bts:

Many of the scenes for the Cat King's residence were shot near the historic Gulf of Georgia Cannery- either on the nearby public wharf or the private building beside it. For the scenes with the cats, the wharf facing the ocean has been replaced in post-production.

The building is privately owned by Coldfish Seafood Co. and is listed as a storage space. It is sometimes rented out for filming. Besides Dead Boy Detectives it has also been featured in 'Once Upon a Time' and 'Power Rangers.'(2017).

Dead Boy Detectives often filmed interior scenes on location, and with the throne room so closely matching the building architecture I think it is safe to assume all of those scenes were filmed here. This has been further confirmed by George and Jayden via cameo.

If you want a better vantage point of the docks/storage building, the Gulf of Georgia Cannery has an outdoor walk that overlooks the area. The GoGC has plenty of local history and I had a great conversation with the staff about the cannery and the filming industry in Steveston.