How did Lindsay feel about Halstead's ex-girlfriend coming back into his life?
That was addressed on Chicago PD Season 4 Episode 17 when Halstead was shocked by the sudden arrival.
Meanwhile, intelligence investigated when they got reports of a woman running barefoot through the woods and found a victim locked up in a shipping container.
Did they manage to find out what was going on?
Use the video above to watch Chicago PD online to get caught up on the drama for the characters in this spin-off series of Chicago Fire.
Paul Dailly is a staff writer for TV Fanatic. Follow him on Twitter.