WWE Hell in a Cell: 3 Wrestlers Who Could Make Shock Appearances
#2 Rey Mysterio
Mysterio's return is something that will happen, it's just a question of when. 'All In' has passed and Mysterio is currently not contracted to any company. He seems to be finished with Lucha Underground and interest from IMPACT never came to fruition.
WWE wants Mysterio to return due to the reception he received during his surprise appearance at January's Royal Rumble and Mysterio himself wants one final run. Whether Mysterio finally returns on Sunday is anyone's guess, but at least we know that he is WWE bound regardless.