Ep 20. Memento

In season 6 episode 20 of Stargate SG1 titled "Memento," Colonel Jack O'Neill and Dr. Daniel Jackson wake up in a white-walled room without any knowledge of how they got there or what happened to them. They soon realize they are in an off-world alien laboratory with a device attached to their heads that continuously erases their memories every few minutes.

As O'Neill and Jackson struggle to remember who they are and why they are there, they discover that they are not alone. Several other individuals, including SG-2 members and even villains they have encountered in the past, are also trapped in the same memory-wiping situation. Together, they must work to unravel the mystery behind their captivity and hopefully find a way to escape.

The episode is a unique departure from the show's usual sci-fi action and adventure, instead favoring a psychological thriller approach. The characters' desperation to reclaim their identities and flee their captors creates tension and urgency throughout the episode. Each new memory wipe adds an additional obstacle for the characters to overcome, driving the sense of danger and helplessness.

Meanwhile, back at Stargate Command, Major Samantha Carter and Teal'c race against the clock to locate their missing teammates. They eventually make a breakthrough in their investigation and discover the alarming truth behind the device's creation and purpose.

As the memory wipes continue, O'Neill and Jackson's memories slowly begin to piece themselves together, revealing startling truths about their situation and the motives of their captors. The final act of the episode is a thrilling race against time as the characters work to escape before their memories are erased for good.

Overall, "Memento" is a standout episode in Stargate SG1's sixth season, masterfully blending a captivating mystery with the show's beloved characters. The unique storyline and fresh approach make it a must-watch for sci-fi fans and Stargate SG1 enthusiasts alike.