I look into the TTTE Wattpad multiverse and rank a bunch of the AU's on the darker side of the galaxy.
If that description didn't make any sense, then that's okay because it's not meant to be taken seriously.
In "Sodor Echo," Thomas and his friends are on the Island of Sodor when they discover a mysterious echo in a part of the island they've never explored. The echo makes strange and unsettling noises, causing Thomas and his friends to become frightened. As they investigate, they imagine all sorts of scary creatures and situations. With the help of their friends and by confronting their fears, they eventually uncover the true nature of the echo and learn a valuable lesson about courage and teamwork.