When after 9 years into the infamous soap opera all of Adam Carrington's siblings - Steven, Fallon, Amanda, and Krystina - had been replaced by other actors, the latter three without explanation, the producers reversed the only explanation of Steven looking differently because of drastic plastic surgery after an ugly oil rig explosion. They aimed to outdo Dallas' dream season with the return of dead Bobby Ewing to become the talk of the nation.
So they deemed Adam to be the culprit behind it all, not even being a sibling of them!
He was supposed to be an alien that could shape shift buildings and rework peoples' memories of who they really are, replacing them all the time. For whatever reason.
They had already made Fallon survive a plane crash, but getting the new one abducted by alien Adam, and made even the new Amanda disappear and not remembered by any of the Carringtons. They had also already revealed Adam not be the son of Blake and Alexis.
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