A catastrophic collapse floods Grey Sloan Memorial with trauma patients and requires all hands on deck. Find out what other fallout occurred on tonight’s Grey’s Anatomy season 11, episode 23.

Case of the week: A tunnel collapse traps a victim in his car and causes massive destruction

New life enters the hospital when a fresh batch of baby chicks and ducks (surgical interns) begin to waddle behind their resident surgeons. Webber takes the baby-faced interns into the OR and gives them the speech that most Grey’s fans can recite from memory. “Today you are the doctors.”

Unfortunately, today is not the day for anyone to adhere to roles they woke up thinking they would fill. Richard and Catherine are no longer bride and groom. Jackson and Bailey are not the maid of honor and best man, respectively. Meredith is no longer a doctor on probation, Owen is no longer Chief, and one new doctor is not exactly clutching his M.D. just yet.

In the locker room, Edwards surveys the crop of interns and sees her lot is not the cream of the crop. She is left with one chatterbox, one white as a ghost, and another too busy shaking to realize where he is. As she leads her gaggle down the hall, another follows close behind Owen. With funding up in the air for the neonatal facilities, Arizona wants Owen back in the Chief’s seat to pull the trigger. But they are barking up the wrong tree as Owen announces he will not be returning as Chief.

Catherine Avery’s hair is looking good as she prepares for her wedding day. Avery’s crumb-filled shirt, on the other hand, could use some dusting as he attempts to provide emotional support as his mother’s maid of honor. Whether she wants to run away or walk down the aisle is a decision for another day as breaking news calls them both back to the hospital.

Webber decides it isn’t the day for a wedding either as the ambulance bay calls for all hands on deck to greet what turns out to be nothing more than hearses with medical equipment. One ambulance does make it from the scene with a survivor. A woman, 40 weeks pregnant with a fractured spine, was pulled from a crushed vehicle, but her husband was left behind. Another victim, a teenager named Scott, is revived in time for Owen, Jackson, and Karev to keep him that way.

Out in the field, April, Meredith, Maggie, and Amelia tend to the fiancé who is impaled in two places, bleeding into his chest, and is fighting not to suffocate. Amelia and Maggie hold out hope that there is a way to get him out of the vehicle and save his life. Meredith does her best to work on the abdominal wounds, but her conversation is the only comfort she can offer Keith. She makes the call to black tag him and get back to the hospital where they can be of more assistance. April offers to stay.

Keith’s trauma causes less of a fuss than Scott, who is not going to make it to the OR in time. Owen suggests they remove the patient’s blood, replace it with saline and cool his body down into a state of suspended animation. Catherine and Jackson are adamantly against this procedure, since it is a risk they are taking without parental consent. Richard, however, still has a role to play as interim Chief and gives the go ahead to Owen and Alex. Jo has another opinion that weighs heavily, but the doctors are already draining Scott’s blood. His friends overheard the doctors discussing the procedure and pulled up research that reveals the procedure has never had a published human trial. But the pigs lived!

Keith’s fiancé is stabilized and her contractions are making it hard to keep her in that state. She and Keith met nine months and three days ago. You could say they did things a bit backwards. Just like the doctor who happened to be on the scene and accompanied the ambulance to Grey Sloan Memorial. Andrew DeLuca quickly fills the void left by Derek Shepherd in the hot doctor quota for the series, but his looks and quick thinking are not going to keep him in the good graces of the doctors for long.

Meredith returns to the hospital and her happy little bubble bursts when Amelia takes a pin to it. Amelia takes the call Meredith made in the field as the perfect gateway to finally address why she was not consulted after Derek’s death. Meredith floats through the assault of questions, but cannot keep up her strength long after.

Owen and Karev finish their surgery and get the kid’s heart beating again. One success in the OR is a rush that Jo is looking for more of in her life. But will crisis after crisis on a tour of duty be too much of an adventure? For Alex, it most certainly would be. For the first time in his life he put down roots. He has Meredith, he loves his job, but if Jo wants to leave and take a year off, who is he to stop her? It is Alex’s roots that Meredith hopes will help ground her and her kids.

Since April returned from combat, April is not the woman Jackson married. Work seems to come between more than a couple of relationships. Richard, yet again, takes stock of his life and realizes the same pattern is happening with Catherine that happened with his other two marriages. Work trumps romance.

As the series heads into the finale next week, there are a few loose ends that need to be tied up:

•April took charge in the field and brought the entire car, with Keith still alive inside, to the hospital.

•Bailey, Arizona, and Catherine Avery take a good look at the leadership of Grey Sloan Memorial.

•Edwards’ interns remain a hot mess and Andrew DeLuca has a lot to answer for.

Watch the Grey’s Anatomy season 11 finale, “You’re My Home,” Thursday, May 14 at 8:00 p.m. ET on ABC.