Nathan Fillion's appearance has fans concerned ahead of season four of The Rookie

What happened to him?

Nathan Fillion caused a stir with a new selfie ahead of filming for season four of his hit show, The Rookie.

The Suicide Squad 2 actor had his social media followers concerned when he shared a photo in which he was sporting a mystery injury. 

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The Instagram snapshot showed him with two painful-looking cuts on his face and he captioned it: "I cut myself shaving. Don’t ask me how- I use an electric razor."

Fans immediately responded and wrote: "Ouch. Looks so painful," and, "man, looks like he got in a fight with Freddy Krueger".

Fans weren't sure if it was real or fake 

Others were convinced it was makeup and added: "Stage blood surely… if not, yikes - bin the razor, and stay away from all sharp objects."

Nathan's image also sparked excitement as fans wondered if he was back on set and shooting season four!

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"Wait what if it’s stage makeup they are starting to film season 4!?" one of his followers asked, which led to a huge response from others as well. They exclaimed: "The Rookie is back!" and, "this is so exciting".

There are big changes coming up for Nathan's character in the new season 

There's been plenty of speculation that filming is kicking off on the new season any day now. 
Season three ended on a cliffhanger and The Rookie's showrunner, Alexi Hawley, revealed Nathan's character, John Nolan, has some big changes coming up. 

John will no longer be a rookie or in training and this changes a lot for him. Alexi told TVLine:

"It's exciting going into season four with things that we haven't done before, with dynamics we haven't put together. Also, what's inherent in not being a rookie or a student or a trainee, is that he'll have a bit more strength because he's going to be the one making the calls."

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