Stargate peaked years back it relies on a set of formulae per epsidoe ala startrek. In trek you had a set numbre of possible plot lines. >>
Alien being traps ship, Enemy Beings take over ship/infiltrate crew, Time travel, Transporter mishap, Aliens hold away team prisoner on a planet, Crew rescue, Alternate universe /alternate enterprise appears or captain gets laid.
I'm sure i can think of more but they all fit into that mould.
Stargate has>
*SG1 finds tech-fights baddies
*Aliens hold SG1 prisoner
*SG1 saves stupid natives from big bad aliens
*SG1 finds tech, loses tech calls asgard for help, asgard pwn all
*SG ALpha site/Outpost gets pwned hours later SG1 turn up *spooky*
*SG1 bring virus/parasite/alien device to cheyenne mountain and avert nucular quarantine by seconds
*Jafar (?) send SG1 on a mission cos theyre too lazy to do it themselves
*SG1 kill system lord/mothership