'Agents of SHIELD': [SPOILER] Returns

Tonight's episode of Agents of SHIELD ended with the character return that fans have been waiting for.

Spoilers for the Agents of SHIELD episode "A Life Earned" follow.

After sitting out the first three episodes of the season, Leopold Fitz finally made his first on-screen appearance in Agents of SHIELD Season Five in the tag to the episode "A Life Earned."

Agents of SHIELD Season Five picked up where Season Four left off, with the team being taken into custody by a mysterious organization. However, Fitz was left behind at the counter of the restaurant they had all been eating because he wasn't on "the list."

Those SHIELD agents who were taken into custody were forced into contact with a monolith similar to the one that had previously sent Jemma Simmons to Maveth. However, the team eventually discovered that the space station they landed on wasn't far from Earth at all. Instead, the monolith that they were forced into sent them forward nearly 100 years into the future.

That's when the first clue from Fitz emerged. The team had taken a postcard for Lake Ontario from the pocket of Virgil, the SHIELD devotee who found them when they first arrived. At first, they didn't think much of it. However, later on, they flipped it over to find a message from Fitz assuring them that he was "working on it."

Considering Fitz was left behind rather than sent through the monolith, the first theory to pop up was simply that Fitz had written this note in his own time and helped propagate the mythology foretelling SHIELD's return. By doing so, he could help ensure that his message would survive through the years as a sacred relic of SHIELD and reach his friends when they emerged on the other side of the monolith's time travel journey.

However, Fitz' appearance at the end of "A Life Earned" throws several new wrinkles into the mix. Fitz does not look like he has aged at all. Moreover, he unmasked right in front of Kasius and calls for Daisy to be forced to fight to the death.

It's possible that Fitz managed to time travel to the future sometime after his friends already went through the monolith. Time travel via monolith being an inexact science, its possible he arrived earlier than they did and in a different location.

Then again, last week's episode of Agents of SHIELD did introduce the multiverse theory, so perhaps this Fitz isn't the Fitz who was left behind at all, but rather the Fitz from the timeline where Quake destroyed the Earth. He may actually want her dead, if that's the case, though that theory does nothing to explain why Fitz isn't 90 or more years older.

The title of next week's episode of Agents of SHIELD is "Rewind," and the synopsis teases both the return of Lance Hunter and an explanation of how Fitz managed to find his lost team, so it sounds like fans won't have long to wait for an answer.

Marvel's Agents of SHIELD airs Fridays at 10 p.m. ET on ABC.