Spider-Man's not taking any chances ... he's got a mask on over his mask, and he's encouraging everyone else to follow his lead.
Tom Holland just whipped up a frenzy on social media with his latest post -- not only is he promoting responsible behavior amid the ongoing COVID-19 pandemic ... but he provided a first look at his character in 'Spider-Man 3.'
Holland's photo shows Spidey in an action pose, in front of a blue screen, wearing a medical facemask over his suit. Tom says ... "Wear a mask, I'm wearing two..."
The pic's also notable for another reason -- it's got diehard fans of the film franchise clamoring to find out who that is standing next to Spider-Man.
Holland and his costars -- including Zendaya and Jacob Batalon -- began filming the upcoming sequel in Georgia this week ... though plot details of the Marvel movie have been kept under wraps.
It's expected to shoot through the winter and be released in December 2021 ... if everything goes according to plan.