You might be sleeping with the light on after watching the Christmas special of Sherlock.
Because according to actress Amanda Abbington it’s going to be properly terrifying.
Speaking to Digital Spy, Amanda said: ‘It’s a proper gothic horror, it’s properly scary edge of your seat and it takes it back to the original.’
The actress returns as Mary Morstan, wife of Watson – played by her real life husband Martin Freeman – in the Victorian version of the popular BBC drama series, in which Benedict Cumberbatch leads as the genius sleuth.