We’re used to seeing Robert Downey Jr. help humanity as both Iron Man and Sherlock Holmes. So it is appropriate that star will be lending a hand to the nonprofit cinema Cinefamily by attending today’s 2nd Annual Fantastic, Elastic 24-Hour Holiday Telethon held at the organization’s home, the Silent Movie Theatre in Los Angeles.

Downey isn’t just attending the event. At 1 p.m., he will be opening a time capsule left for him by parties unknown that was discovered under the Silent Movie Theatre’s projector. So how exactly did the folks at Cinefamily convince the blockbuster star to turn up? “We asked him,” laughs Cinefamily cofounder Hadrian Belove. “Seriously, we asked via friends-of-friends-of friends saying, ‘We found this time capsule, could you come by and open it for a telethon?’ And he said, ‘Yes, I can do it at 1.’ And I said, ‘I guess we’re starting the telethon at 1!'”

Belove says he has no idea what might be in the time capsule. “We’ve got a little bit of Al-Capone’s-vault going on,” he says, referring to the live 1986 televised fiasco, in which Geraldo Rivera opened the infamous gangster’s secret, and as it turned out empty, repository. “I really don’t know what’s in it. It seems to have been left there by fans of Robert Downey. We are opening it early — the plaque said it was to be opened in 2017. It could have the Ark in it. It could be empty, and it’ll just be a great conversation starter.”

Over the last couple of years, Cinefamily has gained a reputation amongst local movie fans for what the LA Weekly once described as its “pathologically idiosyncratic programming.” Certainly there aren’t many other organizations that can claim to have screened both a John Cassavetes retrospective and the so-bad-it’s-fantastic Birdemic. Belove explains the money raised by the Telethon will hopefully pay for a new digital projector but that the event is also an opportunity for the organizers and Cinefamily regulars to just have some fun. “We are raising money to continue doing what we do, to fight the good fight for the arts” says Belove. “But it’s our holiday party. We’re going to have vittles and libations. The point is to come down and have a good time.”

Downey is by no means the only star who will be appearing at the Telethon, for which entry is free on a first-come-first served basis and which will also be live streamed on the Cinefamily website. Other confirmed talent includes Nick Offerman, John Hawkes, Dave Franco, Eric Wareheim, and Jason Schwartzman, who will close out the event on Sunday by allowing attendees to watch him eat lunch. “Actually, we’re having lunch with him,” corrects Belove. “One of my programmers is an old school friend of his. So the idea was that they would catch up over a meal. Then Jason said, ‘Well, it’s going to be weird eating in front of a bunch of people. ‘ So we’re going to have a big potluck. It wouldn’t be Cinefamily if the audience wasn’t participating as well.”

You can find out more about the Telethon, and make a donation, at the nonprofit’s Kickstarter page.

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