French league leaders Paris Saint-Germain have launched a live treasure hunt in London ahead of the club’s Champions League tie with Chelsea.

Using the hashtag #TreasureHuntInLondon, they’re broadcasting a video on Periscope with their location and inviting fans to come find them. They’ve three David Luiz jerseys to give away in honour of the defender being a former Chelsea player.

The first shirt was located by the River Thames, and went to the person who successfully identified where they were and turned up.

It’s not the only piece of social content PSG have posted in the build-up. The club have also been running a Photoshop challenge on Twitter in which fans were asked to imagine their players as main characters in films. This challenge was embraced by their 3.27m followers, with PSG retweeting their efforts.

The club also had their own fun, comparing their players’ performances in the first leg to moments from films under the hashtag #PSGBlockbuster. Goalkeeper Kevin Trapp’s save, for example, was compared to a famous scene from Lord of the Rings.

Since arriving in London ahead of the game they’ve taken to Periscope and Vine to post updates. Players have signed autographs and posed for pictures with fans.