Another planet-of-the-week episode (although it does use a line at the start to remind us of the overarching plot), this time to a world based on the Minoan civilisation of ancient Crete. The world appears to be tidally locked to its star, having a 'light side' and 'dark side', housing the main civilisation and the 'touched', respectively. The touched are a seemingly sub-human race of people, believed to be cursed, who occasionally kidnap the untouched - who may then transform into touched. After an attack by the touched, SG's -1 and -3 return to Earth and inadvertently bring the 'curse' (actually a highly contagious disease) back with them. It's up to the newly introduced Dr. Janet Frasier (Teryl Rothery) to find a cure, which is then also distributed to the 'touched' on the planet.
The Broca Divide doesn't offer much in the way of character development - it does introduce Dr. Frasier though, who will return to the show many times and become a much-loved supporting character. It also expands on Emancipation's establishment of the Sam/Jack relationship by having Carter pounce on O'Neill in the changing rooms. I'm not a 'shipper so I see this mainly as a funny anecdote and strengthening of their friendship, but bear in mind their friendship does develop to something much more powerful in the future.
Despite Daniel's protests that the team should stay on/return to the planet in order to study the culture, the episode doesn't actually reveal much about the small civilisation, its relationship with the touched and their disease, or the relationship to the goa'uld who have apparently been absent for at least a generation. Nor does the episode use its story as a way to explore what makes a person human, despite it being a big plot point. I think the show was still finding its feet at this point and as such created a few weak episodes in its attempts. They're all still enjoyable though, and all add to the background of the world of Stargate.