Board Thread:Spoilers!/@comment-25926288-20160915032911/@comment-24674051-20160915172551

One thing. Regina did not ask for Sydney to become the mirror, but once he did, Regina was more than willing to abuse him, and in fact came to depend on the information that he provided. fast forward to Storybrooke, and Regina still turned to Sydney to dig up dirt (This is how she found out that The Savior was Henry's mom when she was adopting, and also how she got information about Emma after she came to town). Finally, in Season 4, Regina released Sydney from the SB Asylum, and her exact words were "I need my mirror".

And if you consider where we last saw Sydney, he had just been released and rejected by Ingrid. What happened to him since. He's probably been feeling lost and rejected, feeling that no one has a need for him or his services anymore. Not a good place for a former genie, who's served some masters wishes for hundreds (if not thousands) of years.

From just a pure story perspecitve, I could see Sydney either wanting to work with Regina as a means of protection from what he remembers of the Evil Queen, or wanting to work with the Evil Queen as a means of getting revenge on Regina for trapping him in the mirror again. In either case, Sydney would be looking to find new purpose in his life.

So, judging the book (or in this case episode) by it's cover, this looks like it could be a Sydney story. If we get wind that Giancarlo is reprising his role in the episode, that will go a long way towards confirming that suspicion. and if we see Al and/or Jas, it might also confirm that Sydney was Aladdin's genie.