The “Marvel’s Agents of SHIELD” Season 3 finale dropped plenty of shockers, but the final surprise was a big hint at what’s to come in Season 4. Radcliffe was seen launching a program labeled “LMD Phase 1,” and he said it was his computer voice’s birthday. Behind a glass door, it appeared as though Radcliffe had made a person. This will be an important plot point when the ABC drama returns.

LMD is an initialism for Life-Model Decoy, a duplicate of an existing human being. Such humanoid robots play big roles in the Marvel comic books. Many “Agents of SHIELD” fans believed Eric Koenig (Patton Oswalt) and his brothers were also LMDs, but it was never confirmed. In any case, it looks like Radcliffe’s (John Hannah) LMD is going to cause some trouble.

Executive producer Jed Whedon said Radcliffe thinks he is doing a favor for Fitz (Iain De Caestecker) and Simmons (Elizabeth Henstridge). “We can say very little, but we can say Radcliffe, he has a good heart, but he’s dead set on scientific advancement,” Whedon told IGN. “He thinks he’s solving a problem right now, and he says, ‘Fitz and Simmons had friends die, maybe they didn’t have to.’ I think he thinks there might be a solution to some of these problems they’ve faced. Whether or not he’s creating a solution or a new problem, we’ll have to wait [and] see.”

LMDs have caused some trouble in the comic books, as when the LMD of Jake Fury becomes a terrorist known as Scorpio. Plus, Radcliffe turned his own computer, AIDA, into an LMD, which definitely reminds Marvel fans of the film “Avengers: Age of Ultron.” This effort could go very wrong, but that doesn’t stop Radcliffe from making the attempt. (It’s worth noting that AIDA was in the comics as an artificial intelligence system, but she never became an LMD.)

Whedon added that technological advances will be a big part of “Agents of SHIELD” Season 4. When the series returns in the fall, the fear will no longer be about Inhumans invading but instead center on who — or what — is considered human.

“Partially, we’ve been waiting on it because we knew what was coming in the second ‘Avengers’ movie, so we didn’t want to hit that note before them,” Whedon told Variety. “But it’s also a progression of ... this year our theme was ‘Are you Inhuman?’ and dealing with humans without powers and how they react to people given powers, whether or not it ruins them or how that affects their humanity. So now our next progression is ‘What’s beyond humanity?’ and what if you can take those choices into your own hands — what will happen then?”

“Marvel’s Agents of SHIELD” Season 4 will premiere on ABC in a new time slot next fall, Tuesdays at 10 p.m. EDT.

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