Complex sentence: Forced into hiding, McCoy explores the dark, decrepit underworld of 2019 Los Angeles, which allows him to make contact with the Replicant twins Luther and Lance; both former Tyrell employees, and break into the Tyrell Corporation pyramids.
Split into simpler sentences: Forced into hiding, McCoy explores the dark, decrepit underworld of 2019 Los Angeles, and makes contact with the replicant twins Luther and Lance. The twins are both former Tyrell employees, and send McCoy to break into the Tyrell Corporation pyramids.