Complex sentence: Fleming worked for DC Comics initially as a proofreader and later writer, creating "Thriller", and writing an "Aquaman" one-shot special and a limited series in 1989 with plotter/breakdown artist Keith Giffen and artist Curt Swan.
Split into simpler sentences: Fleming worked for DC Comics initially as a proofreader and later writer. Fleming co-wrote an "Aquaman" one-shot special and a limited series in 1989 with plotter/breakdown artist Keith Giffen and artist Curt Swan.