Complex sentence: Malcolm returns to Starling after hearing that Moira was killed by Slade Wilson and arrives in time to save Thea from Slade's minions and convinces Thea to go with him after saving her.
Split into simpler sentences: Malcolm returns to Starling after hearing that Moira was killed by Slade Wilson and arrives in time to save Thea from Slade's minions. He then convinces Thea to go with him after saving her.