Remember how Jean Grey watched as her clone Madelyne 'Goblin Queen' Pryor died during the final moments of the Inferno crossover?
Unfortunately, even in death the evil that corrupted Maddie was a force to be reckoned with. As Jean herself found out while she held her clone's dying body...
The scene of Jean crying out in agony as she holds a dying woman who is closer to her than even the most intimate of lovers nicely mirrors the moment Jean's telepathy first manifested itself... When she was about ten years old, her best friend Annie Richardson was hit by a car and Jean held her dying body while her mind instinctively reached out to Annie's fading consciousness.
Naturally, Jean wasn't able to shield herself from Annie's final thoughts, which caused her to revert to a seemingly catatonic state she remained in until Charles Xavier helped her to deal with her powers. Interestingly enough, Jean had lost her telepathy at the time of Madelyne's death, yet she was affected in very much the same way.
In an attempt to figure out why Jean was in agony, Storm had Psylocke take Cyclops and some of the other X-men inside Jean's mind where they made an interesting discovery.
"Oh Scott, please forgive me. I didn't mean to do that. I couldn't help myself. I've lost control!"
Jean's mind didn't really seem her own any more...For some reason, half of Jean's memory consisted of Madelyne's memories and the Goblin Queen appeared to be the dominant presence.
With her dying breath, Madelyne had successfully managed to transfer and merge her mind with Jean's. But how? Well... the answer is rather Sinister indeed.
"Even if the body lives... the mind... conscious and subconscious, spirit and soul... will be completely obliterated"
The aspect of Mr. Sinister that had invaded Jean's mind was busy destroying her personality so Jean would be a blank slate, ready for him to control her mind in whatever way he felt appropriate.
But even the visiting X-men weren't safe...
"Once I consume your essence... you'll effectively cease to exist. A tabula rasa, Storm, a blank slate, the emptiest of vessels... Which I will then fill to the brim... reshaping you in my psychic image... as I will miss Grey, once I've done the same with..."
It never ceases to amaze why villains don't just skip the exhibition and simply execute whatever evil plot they insist on explaining in the greatest detail beforehand... Their exposition always gies the heroes plenty of time to gain the upper hand.
Sinister was defeated, the X-men returned to their physical bodies and deduced Sinister and his Marauders were hiding inside the ruins of professor Xavier's school for gifted youngsters.
Making their way to Westchester New York, the X-men and X-Factor fought several Marauders, until their leader Polaris showed herself to face off against their assembled might. Needless to say, the Malice possessed mistress of magnetism was no match for the children of the atom...
After capturing Polaris, Storm figured turnabout was fair play so this happened...
Two can play that game... Psylocke forcibly extracted Mister Sinister's actual hiding place from Malice's mind without too much arm wrestling and Cyclops had a final confrontation with the criminal mastermind that didn't involve any mind control at all...
Ahhh, how utterly satisfying it must be to find you can utterly obliterate a seemingly unconquerable, insidious villain just by virtue of who you are... a mutant, born with the ability to fire deadly optic force beams.
Cyclops ended the Inferno crossover by blasting Mister Sinister to smithereens. All's well that ends well, even though this panel basically made Cyclops a killer...
But then again, killing a bad guy wouldn't make him any less unlikeable... not after the way he had previously ditched his wife Madelyne and their son Nathan the second he realised his first love Jean was still among the living... forcefully romancing her while still married and keeping quiet about that for months...
Luckily for poor adulterous Scott Summers, events after Claremont left the book showed he wasn't thát reprehensible... and even a little mind controlled at that...
Mister Sinister can handle optic blasts just fine, he just shifts out of the way. And, as a right of passage he had his Dark Riders kick the crud out of Cyclops.
Serves him right for not sticking to the one red head...