The Deep House (2021)

The British Ben and his American girlfriend Tina are young adventurers that like to look for isolated weird places using Ben's GoPro camera and drone to post in Ben's social media later aiming to reach a great number of followers. They decide to go to France to seek out a lake formed by a submerged town and find that the place is a touristic area full of visitors. They decide to have a drink and leave the spot, but Ben meets the local Pierre that tells that he knows a nearby remote place where there is a n isolated submerged house and Ben and Tina invites Pierre to guide them in their van to the location. Ben and Tina use their diving equipment and drone and find the remote house in the bottom of the lake and decide to explore the place. They find an open entrance and note that the interior of the house is well preserved, not decayed and with all the exits blocked. They also learn that the house belonged to the Montégnac's family (Mister and Madam Montégnac and their daughter Sarah). Soon they find bizarre experiments and Tina asks to leave the house, but they discover that they are trapped inside.