https://www.cnet.com/news/mark-hamill-comic-con-2018-easter-egg/

The Star Wars actor was active on social media during the convention, teasing fans with clues about several costumes to see if anyone could uncover him walking around in cosplay. Fitting for an event full of superheroes with stealth identities.

"FUN FACT: I'M HERE RIGHT NOW!!" Hamill wrote on Instagram. "Here are the 4 masks I'll be wearing (1 for each day) so be on HIGH ALERT & please say hello when you see me!"