Three-year-old Elijah Thomas had just seen a face. And he couldn't have been more excited.

"Look, look," Elijah implored, turning his head to his mother and pointing at a 15-foot metal face about 20 feet away, its mouth opening and closing as the youngster tugged on a metal joystick. "It closed! It closed!"

Elijah's mom, Erika Taylor, laughed and smiled, delighted. "He's having a blast," she said, realizing that the toughest part of her family's visit to Artscape on Friday afternoon would be separating Elijah from the mechanical face that was fast becoming his new BFF.

But that's what happens when you hand over control of a 15-foot stainless steel face to a steady stream of Artscapers. The enchantingly emotive piece is called "Face Forward," and it was fast becoming a hit on the drizzly first day of this year's Artscape, billed as "the country's biggest free arts festival" and running through Sunday on and around Mount Royal Avenue and Charles Street.

"It's fun to control machinery. That's a fundamental thing that I've learned," said New Mexico artist Christian Ristow, who created "Face Forward" about a year ago and has set it up four times, including its debut at last year's Coachella festival in California. "I've had a couple of people today say to me this is the coolest thing they've ever seen. That's nice to hear, and they maybe need to get out more."

Organizers said the opening-day crowd at Artscape was down noticeably, doubtless because of a light but steady rain that fell for much of the afternoon. More precipitation is forecast for Saturday and Sunday. Typically, Artscape draws more than 300,000 visitors over three days.

Still, people seemed to take the wet weather in stride.

"It's no big deal," said Johns Hopkins student Sara Martinez, who came for the afternoon with a few friends, "I just brought my umbrella. We were afraid that it was going to be really hot. This is a lot better than that."

But even at a festival that includes live music, scores of artists selling unique creations and a stretch of Charles Street dedicated to "Roadside Attractions" that evoke a cross-country road trip, "Face Forward" proved a crowd-pleaser. Even the intermittent showers couldn't dampen people's enthusiasm.

From its location just west of the Lyric Opera House, the sound of laughter was a constant. Young and old used wired controls to manipulate its eyes, lips, eyebrows and cheeks, making the androgynous face look alternately seductive or surprised, wide awake or fast asleep, welcoming or threatening.

"It's awesome, dude," said Andrew Myszkowski, who grew up in Govans and had come from New Jersey for the day. Proclaiming it "the best exhibit of the day," he paused a moment to explain what made "Face Forward" so cool.

"You can be part of the art, and that's great," he said. "The piece can stand by itself, but without you, it's a little less."

Five-year-old Liam Fothergill laughed as he manipulated one of the face's eyelids, leaving it closed and giving the whole installation a faintly demented look. He thought the look was "pretty funny," but his mom wasn't such a fan. With an admirable (and perhaps motherly) concern for the piece's aesthetics, she took a moment to manipulate the face, leaving both eyes open and everything nicely in balance.

"I'm going for that pleasing look," she said with an indulgent smile. "He was clearly going for the 'How can I make this as quirky as possible?' look."