Enid-Raye Adams

A highly intelligent serial killer “over there” forces the two Fringe teams to work together as the killer’s doppelganger “over here” is brought into the fold to help.

In the season four premiere, Oliver and Felicity must return home to help the team against attacks by "ghost" assassins led by Damien Darhk (Neal McDonough).

Oliver and the team uncover HIVE's plan to take out Team Arrow once and for all. With HIVE's next attack imminent, Lance wonders if Donna is safer without him in her life. Meanwhile, with the wedding fast approaching, Oliver begins to feel guilty that he hasn't told Felicity about his son.