A new batch of photos from House of the Dragon episode 6, which airs this Sunday on HBO, have arrived — and fans of Doctor Who may recognize one of the actors making their debut.

After a time jump between episodes 5 and 6, we see that young Aegon II Targaryen, the first male heir of King Viserys Targaryen (Paddy Considine), has grown into a teen. That means there's an actor change after viewers saw the character as a toddler in previous episodes. Ty Tennant, 20, will now appear as Aegon in episode 6.