You’ve heard of the film Snakes on a Plane, but now get ready for the social media sensation Snakes Down a Lane, which is panicking Londoners with talk of ‘feral’ serpents by the canalsYou’ve heard of the film Snakes on a Plane, but now get ready for the social media sensation Snakes Down a Lane, which is panicking Londoners with talk of ‘feral’ serpents by the canals