Earlier today, Marvel's The Avengers star Jeremy Renner took to his Twitter account, revealing that he is back in costume as Hawkeye, although he couldn't reveal why. There are likely only two possible scenarios for why the actor is donning his Hawkeye attire once again, either for the previously-reported January reshoots on Marvel's highly-anticipated sequel Avengers: Age of Ultron, or to shoot a cameo or guest starring role on ABC's Marvel's Agents of S.H.I.E.L.D.. While it most certainly could be for the Avengers: Age of Ultron reshoots, there is evidence that suggests Jeremy Renner is heading to Marvel's Agents of S.H.I.E.L.D., at least for one episode.

Last month, Marvel's Agents of S.H.I.E.L.D. star Clark Gregg posted an intriguing image on his official Facebook page, which showed a stand-off between both Agent Coulson and Hawkeye. The image was from Marvel's Secret Avengers #10 comic released back in November, and, while Clark Gregg never said why exactly he posted that image, many fans thought it was a clue that Hawkeye may appear in an upcoming episode. After all, the series has previously featured stars from the Marvel Cinematic Universe such as Samuel L. Jackson (Nick Fury), Cobie Smulders (Maria Hill) and Jaimie Alexander (Lady Sif) in the past.

It's also worth noting that, just a few days ago, Ming-Na Wen (Melinda May) revealed on her own Twitter account that she is going back to work this week. On the other hand, we've known since November that director Joss Whedon is assembling Earth's Mightiest Heroes for a round of reshoots at Pinewood Studios in the U.K. this month, although it wasn't specified exactly when the shoot will take place. Regardless, Jeremy Renner suited up as Hawkeye for... something, today, so hopefully we'll learn more details soon.