Well, this is sneaky—and for some, a little heartbreaking.

Tinder users at the SXSW festival on Saturday were encountering an attractive 25-year-old woman named Ava on the dating app. A friend of ours made a match with her, and soon they were having a conversation via text message.

But when he opened up Ava's Instagram, it became clear something was amiss. There was one photo and one video, both promoting Ex Machina, a sci-fi film that just happened to be premiering Saturday night here in Austin. The link in her bio went to the film's website. And it turns out the woman in the photos is Swedish actress Alicia Vikander, who plays an artificial intelligence in the movie.

It's pretty brilliant in the way it ties into the movie. Only in retrospect do you realize that Ava's questions are about a robot wanting to know what it's like to be human.

It's also pretty invasive, and some will call it spammy. If you think about it, it's only a step above Tinder's porn bots. In this case, though, I'd give it a pass because it's such a strong fit conceptually. She's a bot in the movie, so of course she's a bot on Tinder.

As for our friend—whose texts above, we can attest, were totally heartfelt—he found the whole thing impressively deceptive and shared it with others. But he was also a little crestfallen. It "toyed with my emotions so hard," he says.

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