Taken from Spoilerfix.com
Don't read if you don't want to be spoiled:
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The series was renewed for a fourth season of 13 episodes.
02/21 - Episode 4.01 - The Wrath of Graham [Airing June 17]: This episode seems to be set a few months after the Season 3 finale. Tom is looking for Alana and seems to be at a dead end when he is told that a prisoner, who may have leads for him, is now allowed to see visitors. A student named Graham is surprised when his classmates agree to play any sports he wants (thumb wrestling anyone?) in gym class. Could he have the power to have anyone do anything? Kyle gets a new job: helping out the 4400 as legal aid. Shawn is at the hospital (as a patient) and has terrible convulsions. Kevin, Susan, Shawn, Marco, Brady, P.J., Diana, Maia, Tess, Ben, Garrity, Jordan, and Isabelle also appear. Source: SpoilerFix.com
04/05 - Episode 4.02 - Fear Itself [Airing June 24]: People start seeing what they fear most (a man sees tarentulas crawling over him, a woman sees walls being put around her); however, only they can see these things. Tom's investigation leads him to a bank as a few of the victims used the bank's ATM before the "fear" attacks. Isabelle may get a better living situation if she agrees to be injected promicin. Kyle doesn't want to be part of some sort of religious revival involving the "White Lights" cult. Shawn, Diana, and Garrity also appear. Source: SpoilerFix.com
05/03 - Episode 4.03 - Audrey Parker's Come & Gone: During this episode, 70-year-old Audrey Parker, via voice over, explains her past and why she decided to take promicin at such a late age. Thanks to promicin, Audrey develops the power of astral projection... with a twist. Audrey cannot astral project her 70-year-old self but the 25-year-old version of herself. This power will allow Audrey to do all the things she wanted to and never had the chance to before. Audrey's positive experience with promicin is told on a blog. Diana and Tom are put on the case. Shawn meets with 4400 Heather Tobey (episode "Suffer the Children"). Meghan appears. Source: SpoilerFix.com
05/19 - Episode 4.04 - The Truth & Nothing But The Truth: We finally see April Soukris again after taking promicin and being on the run for four months. Let's say that the woman changed a lot and, of course, has developped a power. April will use her power to help Tom and Diana work a case. Source: SpoilerFix.com
04/26 - Episode 4.05 - Try the Pie: Shannon Reese, a patient and lovely woman in her 30s, will teach Tom about her neighbors, who all took promicin. Shannon has the ability to remove stress in people's lives by listening to their problems. At the end of their meeting with Shannon, their problems are all turned into a small jewel. Tom doesn't seem to approve much of the fact that this town, Evanston, seems to have given promicin to all its inhabitants. Source: SpoilerFix.com
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