5) General Hux Is Luke’s Son Attempting To Destroy The First Order From Within
The rumor that Domhnall Gleeson’s First Order commander General Hux is secretly Luke Skywalker’s son was apparently borne of two things. First is that Gleeson bears a passing resemblance to a young Mark Hamill. Second is a leaked synopsis – featuring Hux’s First Order infiltration as a plot point – that has long since been debunked.
These are very weak bases for such a wild theory, made weaker by the fact that Gleeson has spoken of Hux’s power-hungry character, calling him “messed up” and “ruthless.” It makes no sense that someone trying to bring down the First Order from the inside would be a merciless killer that at the same time is strengthening the organization.
Besides, at this point it looks more likely that another prominent First Order leader is the real secret Skywalker – to have two just seems like over-egging it.