Stargate Atlantis (2004)

S4E6 Tabula Rasa

In the episode "Tabula Rasa," a mysterious virus sweeps through Atlantis, leaving everyone except Teyla and Ronon suffering from severe amnesia. As the team grapples with the loss of their identities and essential memories, Teyla and Ronon take the lead, racing against time to uncover a cure. With their friends in peril, they must navigate the challenges of a memory-less Atlantis and work collaboratively to restore what has been lost before it disappears forever.