“Fifty-Fifty” is episode thirteen of season three of The 4400 and the season finale.
Alana finds Tom up in the middle of the night going through things Kyle left behind. Devon is in a house, being videoed as she takes some of the promicin Jordan Collier had stolen in the previous episode, “Terrible Swift Sword”, and telling those watching that she will be a 4400.
At NTAC, Jarvis is showing them the video – Diana recognises Devon – and Tom says Collier doesn’t seem to care if they come for him. He’s creating a market for the product. On the video, Devon says that shots will be everywhere soon.
NTAC heads to The 4400 Centre and doesn’t find any promicin there. Collier denies knowledge of where Devon is but would congratulate her for what she’s doing. Diana and Tom tell Shawn there will be chaos everywhere; Shawn doesn’t agree with their viewpoint. He says the Centre is being contacted by people wanting promicin but they don’t know where to get it. Diana decides to take Maia out of class.
Ryland is watching the video with Isabelle; she’s annoyed and wants to move against Collier. Ryland is not annoyed; he says if the promicin is on the street then Collier is doing their work for them.
Maia and Diana are at home; Maia is not happy about being dragged out of school. Ben arrives and Diana says she’s in the middle of something. Maia storms off. Okay, maybe she’s free. Ben has a job offer in Spain. It will take six months. And he wants Diana and Maia to come with.
At NTAC, Marco has been working on the background noise in Devon’s video. He’s narrowed down the location a lot. At the house, Devon is in bed, telling Tess she feels weird. Tess says that Kevin Burkhoff went through the same thing, but Ryland’s promicin is pure and it will go easier for Devon. Tess heads outside and is talking to Burkhoff and how they will soon be heroes when Devon screams. Burkhoff heads in and tells Tess to get Shawn. Devon is bleeding from her eyes and nose. At NTAC, Diana has found a potential house. At the house, Shawn is trying to help Devon when Tess sees NTAC approaching. Shawn won’t leave Devon as the others head out, but when Diana and Tom find him, Devon is dead. Shawn is taken back to NTAC, but won’t say anything more.
Jordan Collier tells the others that Devon isn’t the first sacrifice the future has asked for and she won’t be the last. Richard wants to destroy the promicin and leave before NTAC gets there. Collier says Shawn won’t talk; Richard thinks the government will get the information anyway. Collier still wants to distribute it; Richard objects because it killed Devon. Burkhoff thinks it’s a dosage problem; the promicin from Isabelle is different, too pure. Richard decides to end this, but he’s the only one. He starts destroying the promicin with his power until Tess stops him with hers.
Maia is still ignoring Diana. April returns; she’s brought their mother’s engagement ring back.
Tom and Diana head to see Ryland. He admits there were some casualties amongst the volunteers. Half of them died, in fact. Ryland didn’t tell NTAC so that Jordan Collier would publicly fail.
There’s the titular fifty-fifty chance between ending up a 4400 or dead if the promicin is taken. And those are odds that some will think are good enough. Isabelle is becoming increasingly scary and even Ryland starts to realise just how dangerous she is.