No idea. I read Strange Adventures #1 and was a bit confused in parts, but I pieced things together well enough. Apparently the church from Captain Comet's rebirth series went on to unleash some kind of godlike dude on Rann, Adam Strange saved the people but wound up blowing the planet's atmosphere away while getting rid of the villain, and now the Rannians are hanging out on Throneworld, which somehow lost its population.
So now we've got the Rannians and Throneworld in an alliance, the Throneworld Starman dude trying to convince everyone that his people are still on the planet, the Rannians trying to ascertain whether Adam Strange is a traitor for inadvertently destroying their old planet's atmosphere, Comet hanging out on Hardcore Station again, and the Weird or the church (not sure) recruiting Bizarro for... something. It's a bit confusing and continuity-heavy, but I'm sure I'll figure things out as I go along. The one bit that totally perplexes me is the Weird's involvement.