"Lockdown" is about the discovery of an outbreak of disease which first occurred in the Russian Federation, but later on infects personnel of Stargate Command.
At the same time, Jack O'Neill stops the recruiting process for SG-1 leaving Samantha Carter as the new leader of SG-1 throughout season 8.
Anubis tries to take new hosts but is eventually defeated and forced to a destination chosen by Carter, a frozen, barren planet.
Daniel suddenly pulls out his gun and injures several people, yelling for the gate to be opened, before he is stopped by O'Neill and Teal'c.
The members of SGC conclude that Anubis plans to leave through the stargate rather than use his ascended powers, since that would draw attention from the Ancients.
However, Anubis takes over Carter (who is in the section controlling the "lockdown"), and makes her schedule a program to open the doors temporarily.
Afterwards, Carter reveals that Anubis did not actually escape, as she did manage to override the dialing process to send him to an alternate address.
The planet she chose to send him to was extremely cold, so Vaselov's body froze, leaving Anubis unable to dial a new address.
One of the early scenes featuring Alexi Vaselov, where he awakens to find Teal'c in the observation room, was originally scripted to take place in the infirmary.
"Lockdown" drew close to 2.7 million viewers in the United States, this was down four-tenths from the previous episode "New Order".