Earlier this month, we learned that Pedro Pascal would be joining the cast of the acclaimed HBO fantasy series ‘Game of Thrones’ playing the Red Viper in the fourth season. Now, Entertainment Weekly tells us that another star has just been added as well and if you’re familiar with practically every popular BBC show right now, you’ll know his name.

In some corners of the internet, fans may dream about a ‘Doctor Who’, ‘Sherlock’, and ‘Game of Thrones’ crossover, but now that dream is becoming a reality (sort of) because British writer/producer/actor Mark Gatiss is the latest addition to ‘Game of Thrones’. Probably most recognized for his role of Mycroft Holmes in the vastly popular ‘Sherlock’ starring Benedict Cumberbatch and Martin Freeman, Gatiss also co-created and writes the show with Steven Moffat in addition to writing a number of things for the last of the Time Lords like novels, radio plays, television episodes, and the 50th anniversary docudrama, ‘An Adventure In Time and Space’. And when he’s not contributing to arguably two of the BBC’s biggest shows ever, he’s also making other acting appearances in things like ‘Spaced’, ‘Being Human’, and more.

With an already extensive fandom resume, Gatiss is now booked for a strictly acting role in ‘Game of Thrones’. Unfortunately, the character that he will be playing is being kept under wraps. However, the information may be revealed this weekend during San Diego Comic-Con when showrunners David Benioff and Dan Weiss take the stage for their panel to discuss what’s next for the George R.R. Martin adaptation. Additionally, Gatiss will be present at the con as well for the ‘Sherlock’ panel, so maybe we’ll get the reveal straight from the horse’s mouth. Either way, if the news gets out, we’ll be sure to let you know about it, faithful readers!

Despite not knowing who he’ll play, what do you think about Mark Gatiss joining Season our of ‘Game of Thrones’? Do you have any ideas as to who he could be? Share your theories in the comments below.