During Comic-Con International, it was revealed that Mark Gatiss of Sherlock fame will have a role to play in the coming season of Game of Thrones. At the time, speculation on Gatiss' character ran the gamut from Mace Tyrell of Highgarden to the mythical Coldhands beyond the Wall. Turns out, Gatiss is playing someone else entirely — a man with very specific business in Westeros.
According to the fan site WinterIsComing.net, Gatiss has joined Thrones as Tycho Nestoris, a representative of the Iron Bank of Braavos. In the world of Thrones, the Iron Bank is notorious for always getting back the money it lends, one way or another. That's a lesson the Lannisters might learn firsthand, as King's Landing and the Iron Throne are greatly indebted to the Iron Bank of Braavos. (What is it they say about Lannisters and debts again?)
In George R.R. Martin's A Song of Ice and Fire novels, Tycho isn't introduced until A Dance with Dragons, the fifth book in the series. With Gatiss cast as the character, Tycho's television counterpart appears to be a much bigger deal than he currently is in the books. It's certainly an interesting and surprising development for fans of both the novels and the shows to keep an eye on.