Kendra's team at the TSIB soon figures out all the companies that gained from the crash are affiliated to a man who is not related to Moreau, Howard or even Janet for that matter
Spoilers for 'Departure'
After a very exciting first 30 minutes, there's a gigantic twist in the tale of Peaco*ck's 'Departure' that comes following the big arrest. Aviation investigator Kendra Malley (Archie Panjabi) arrests her former boss and mentor Howard (Christopher Plummer) for co-conspiring with airline owner Ethan Moreau and MI5 operative Janet.
The trio had targetted Kendra's stepson AJ, and later her too, to stop her from seeking the airplane's black box which would reveal incriminating audio from the co*ckpit and thus, hold the airline company responsible for the crash. Yet, in the final moments of the show, Kendra turns her suspicions to someone they had doubted a while ago — in fact, AJ had closed the case on that one. Looks like Moreau and Plummer aren't the ones behind the crash after all, and here's how everything goes down.
In the season finale, Episode 6: 'Endgame', Kendra arrests Moreau for not fixing the glitch in the airline's software that had been pointed out by his employee, Hoffman. Hoffman would carry out in-flight simulations to check the craft's capacity to endure a possible threat and the crash happens when one of those simulations goes awry.
Teaming up with MI5 and the TSIB, Hoffman's boss Moreau tries to pin the blame on the Mossad agent onboard the flight, Hassan Esmaili, as his voice was the last one recorded from the co*ckpit, via the very dangerously acquired black box from the ocean. Noting how quick to jump to conclusions Howard was, the rest of the team investigate the matter deeper and dig out Hoffman's involvement, and obtain a statement from the flight's lone survivor Madelyn Strong.
Madelyn recollects seeing the entertainment channels on the flight falter because the screen turned to a security error message, called "MOSIS". During the commotion, Hassan requested the pilot to let him in as he had military flight experience and claimed he could help. The engine had to be turned on manually, and when the pilot finally arrives at the designated switchboard, he succumbs to lack of oxygen in the craft. Hassan, getting no response, resorts to his final prayers of "Allahu Akbar" before the flight crashes.
All of this is enough to hold Howard and Moreau accountable, and with Janet dying from a physical altercation with Kendra, only the two men get punished. Yet, things change when AJ realizes he was unnecessarily suspecting and targeting another airline owner Pavel Bartok for causing the crash. AJ, after recovering from the near-fatal attack, goes to apologize to Bartok in person, but the entrepreneur is too kind and compassionate about whatever the young teen did.
Suspiciously enough, Bartok also tells AJ that he knew Kendra would figure it out all along if she "stuck with Hoffman". And when AJ relays that to his stepmother, it doesn't take long for her to connect the dots on having been played.
Kendra's team at the TSIB soon figures out all the companies that gained from the crash are affiliated to Bartok. They also suspect Bartok convinced Hoffman to get on Flight 716 and carry out the simulation that would test the plane's security in a fake-crash scenario, and that's where everything goes wrong. Eventually, through security footages from Heathrow, the team dig out Hoffman's old pal Stevon Tark seeing him off before the fateful journey and offering him a laptop.
Kendra believes Tark put a virus in the simulation software and the attack that would have been regulated by Hoffman, got out of control. The team then looks at possible connections between Bartok and Tark and sure enough, they were the only two engineers to survive another crash long ago.
The season finale ends with Kendra confronting Bartok and him threatening that there's nothing she can prove, but that could be a potential segue for a second season. That doesn't mean Kendra arrested the wrong guys though. Moreau and Howard are still responsible for attacking her, AJ, and covering up their hand in the crash.
Bartok's vested interest in the crash was benefitting from the international deals that pulled out of business with Moreau and inevitably turned to him. His downfall is something a second season could follow.'Departure' premiered on September 17 on Peaco*ck.
