After five seasons filmed across nearly a decade, a show like Stranger Things is likely to face certain continuity errors. The hit Netflix series returned with part 1 of its fifth and final season on Wednesday, November 26, with a scene showing flashbacks of Will (Noah Schnapp) and Mike (Finn Wolfhard). One of the key moments featured Will when he was younger building his iconic Castle Byers with brother Jonathan (Charlie Heaton), which caught fans' attention.