Ultron

The very nature of Ultron – he was essentially a computer programme/electronic consciousness that could jump between robotic bodies – meant that he would be very hard to permanently kill and, although that did appear to be the case, you shouldn’t bank on him being dead.

Ultron was created using (amongst other things) the Mind Stone, which still exists, and although his last drone was supposedly destroyed by Vision, you have to wonder if he actually had a contingency body stored elsewhere or if he had thrown his consciousness into some other technology to save himself.

There is so much more that could be done with the character – he could join a Masters of Evil team, he could upgrade his body further, he could head to space and lead the Phalanx etc – and there’s every chance he could return.

James Spader’s performance went down very well and it would be a shame not to see him again. Don’t rule it out, therefore.