After months of rumors, Shawn Mendes and Camila Cabello of Fifth Harmony have confirmed... something. Just what, we're not quite sure.

The two dropped a 15-second teaser on YouTube, most likely for a track called "I Know What You Did Last Summer." Based on the uptempo beat of Shawn's guitar strumming and Camila's lovely vocals, we're assuming this isn't in reference to the classic teen horror film.

In addition to the song clip, a corresponding website is currently live at ikwydls.com though the page is mostly blank except for a background of "TV static" and the words "COMING SOON." As for now, we'll have to wait to hear both the full track and a confirmation of their relationship.