After Katherine announces that she has to leave town, Bree is left responsible for catering Bob and Lee's wedding. Gabrielle finds $118,000 in Ellie's teddy bear. Susan realizes she will soon lose someone she loves. Katherine Mayfair's secrets are finally revealed, and several residents of Wisteria Lane are faced with deadly threats.

As people across the globe are experiencing hallucinations, MI5 agent Zoe contacts Bill for answers; Catherine Durand detects unusual black hole activity.

As Adina starts the next stage of her plan, astronauts Juliet and Richard see warning signs in space; uncovering Adina's sinister mission.

M.O.D.O.K. suddenly starts acting like a model employee, dutifully delivering mail and making tablets. Austin has a change of heart and tries to inform M.O.D.O.K. who really is running GRUMBL. Thrown by M.O.D.O.K.’s new behavior, Gary thinks it's Austin's fault, and Monica suspects M.O.D.O.K. is planning something against her. Eventually, M.O.D.O.K. reveals that he is selling his shares in AIM to Tony Stark and starts a new business with Monica. Austin misses the chance to tell M.O.D.O.K. the truth about GRUMBL.

M.O.D.O.K. suddenly starts acting like a model employee, dutifully delivering mail and making tablets. Austin has a change of heart and tries to inform M.O.D.O.K. who really is running GRUMBL. Thrown by M.O.D.O.K.’s new behavior, Gary thinks it's Austin's fault, and Monica suspects M.O.D.O.K. is planning something against her. Eventually, M.O.D.O.K. reveals that he is selling his shares in AIM to Tony Stark and starts a new business with Monica. Austin misses the chance to tell M.O.D.O.K. the truth about GRUMBL.

Lou's bar mitzvah doesn't attract many guests, so M.O.D.O.K. is forced to invite the villains and creatures he’s met along the season. Young M.O.D.O.K. attacks and puts the family in a precarious situation before taking M.O.D.O.K. into the time stream. Young M.O.D.O.K. reveals that if M.O.D.O.K. truly wants to take over the world, his family has to die. M.O.D.O.K. is forced to make the toughest decision of his life.

When astrophysicists detect a transmission from another galaxy, it is definitive proof of intelligent extra-terrestrial life. The world's population waits for further contact with baited breath. They do not have to wait long. Within days, mankind is all but wiped out; just pockets of humanity are left in an eerily deserted world.

After the devastating alien attack, disparate pockets of survivors emerge into a shattered world. They quickly realise they must put their differences aside if they are to stand any chance of survival.

As the dust settles on their brave new world, the survivors are forced to face some cold truths. Catherine is stunned to discover the part she played in bringing about the alien attack. Helen becomes fixated on revenge. And Emily momentarily regains her sight. But is the miracle cause for celebration, or concern?

When Devon's patient, who was pronounced dead, suddenly revives, Conrad is left doubting Devon's judgement and wondering what happened. A well-known white supremacist falls under the care of Cain and Nic, causing the two to butt heads on how to move forward. Meanwhile, on their way to a medical convention, The Raptor and Mina get stuck in a strange town, where they uncover new information about Red Rock Medical.

After a plane crashes in Atlanta, Devon is overcome by guilt at the thought that he could have prevented the tragedy. Bell, who was a passenger on the plane, makes it his personal mission to save the life of the man seated next to him. Meanwhile, Adaku returns to ask Mina a big favor, the Raptor struggles with telling his birth parents about meeting his biological father and Conrad and Nic consider risking it all to investigate a drug that might be linked to Jessie’s death.

On National Nurses' Day, Chastain's nurses are severely understaffed and overworked, leaving them all feeling exhausted and underappreciated. Cain performs a dangerous surgery on a new patient he won in a game of poker. Meanwhile, Conrad discovers that his father has been administered the same drug that he fears played a role in Jessie's death, The Raptor comes face-to-face with his birth mother for the first time and Irving attempts to take the next step in his relationship with Jessica.

Diane Pierce returns to Grey Sloan, but Maggie is still in the dark as to why she's really there. Owen and Amelia hash out their problems as they work a trauma case together, and Bailey tries to mend her relationship with Richard.

When Maggie's mom's health deteriorates, the doctors are at odds over how to treat her. Meanwhile, Richard comes to grips with Bailey's betrayal over the Residency Program.

When Maggie takes on a big case, many of the doctors are worried she's not the right one for the job while Stephanie makes a mistake treating one of Grey Sloan's own.

Lives hang in the balance as the members of Station 19 continue to fight a raging inferno inside a skyscraper. Meanwhile, Pruitt's health is in grave danger at Grey Sloan; and a seasoned firefighter with a mysterious past arrives at Station 19, leaving everyone to wonder what the future holds.

It's a life-and-death situation when a young boy falls into water pipes beneath the city of Seattle. With the clock ticking, the firefighters of Station 19 jump into action to save his life.

A mysterious stalker from Adam's past shows up on Wisteria Lane, and they have dinner. Detectives question Gabrielle about Victor's whereabouts. Danielle's baby puts stress on Bree and Orson's marriage. Lynette has a reunion with her long-lost stepfather, Glen. Susan notices Mike is behaving strangely.

A tornado comes to Wisteria Lane, forcing residents into basements, cellars and safe rooms, and destroying homes and lives. Meanwhile, Susan ends up at the hospital after falling down the stairs.

In the aftermath of the tornado, the residents of Wisteria Lane try to rebuild their lives. Katherine discovers someone may know her secret while Lynette faces the possibility of her family's fate.

Megan & Tommy investigate the murder of a young woman, which leads them to her neighbor, who bites Tommy and is diagnosed with rabies. When another rabies fatality comes in without any bite, Kate calls in the new health commissioner to help Megan.

When Melinda meets a nightclub waiter who has not played his guitar since his friend died, she finds that he is being haunted by two ghosts.

Emerald embraces her independence, until an unexpected turn forces the team to unite in pursuit of justice.

The shooting death of a New York mobster's son creates a tense situation when the mobster threatens to find and kill the person responsible. Megan and the team must hurry to solve the case after one suspect is killed.

After Megan questions the grief counselor for one of the victim's parents, she decides to take him up on his offer of counseling her on her own issues about her father's suicide. But Megan is shocked by what she finds in his waiting room.

Kate meets Sergei, a handsome and mysterious guest at a political event, and is irresistibly drawn to him. But when a young Russian girl is found murdered near the hotel where she and Sergei are having a tryst, Kate suspect and turns to Megan for help.

Bree and Katherine decide to start a catering business together. Lynette tries to deny her feelings for Rick. Mike learns the truth about his nearly fatal accident. Carlos gets a seeing-eye dog. Dylan meets her estranged father.

Susan meets her ex-husband, Karl at a Lamaze class, and finds out that he has remarried and is having another child. Lynette learns who was responsible for starting the fire at Rick's restaurant. Bree wants Orson to turn himself in to the police. Meanwhile, Gabrielle rents a room to a hip artist, Ellie, who has a dark secret. Elsewhere, Dylan continues meeting with her father, Wayne, and Katherine decides to go spy on her.

Adele Delfino, Susan's mother-in-law, arrives for a visit. Carlos and Gabrielle find out their tenant, Elli, has a dark secret. A full scale war erupts between Bree and Edie.

The shooting death of a New York mobster's son creates a tense situation when the mobster threatens to find and kill the person responsible. Megan and the team must hurry to solve the case after one suspect is killed.

After Megan questions the grief counselor for one of the victim's parents, she decides to take him up on his offer of counseling her on her own issues about her father's suicide. But Megan is shocked by what she finds in his waiting room.

When Station 19 receives a call from concerned neighbors regarding a resident in their apartment building, the team heads out to investigate. When they arrive to evaluate the scene, they're shocked by what they find inside. Meanwhile, in an effort to create a solid working relationship between the fire and police departments, Ryan takes an unlikely member of the team on a ride-along.

After Megan questions the grief counselor for one of the victim's parents, she decides to take him up on his offer of counseling her on her own issues about her father's suicide. But Megan is shocked by what she finds in his waiting room.

When Devon's patient, who was pronounced dead, suddenly revives, Conrad is left doubting Devon's judgement and wondering what happened. A well-known white supremacist falls under the care of Cain and Nic, causing the two to butt heads on how to move forward. Meanwhile, on their way to a medical convention, The Raptor and Mina get stuck in a strange town, where they uncover new information about Red Rock Medical.

After a plane crashes in Atlanta, Devon is overcome by guilt at the thought that he could have prevented the tragedy. Bell, who was a passenger on the plane, makes it his personal mission to save the life of the man seated next to him. Meanwhile, Adaku returns to ask Mina a big favor, the Raptor struggles with telling his birth parents about meeting his biological father and Conrad and Nic consider risking it all to investigate a drug that might be linked to Jessie’s death.

On National Nurses' Day, Chastain's nurses are severely understaffed and overworked, leaving them all feeling exhausted and underappreciated. Cain performs a dangerous surgery on a new patient he won in a game of poker. Meanwhile, Conrad discovers that his father has been administered the same drug that he fears played a role in Jessie's death, The Raptor comes face-to-face with his birth mother for the first time and Irving attempts to take the next step in his relationship with Jessica.