"Orphan Black" is set to return for a fourth season this year and in honour of all that Sarah Manning and her sestras had lost, the show's creators recently came out with a video that pays homage to them.

The two-minute video, which bears the title "Orphan Black S1 - S3: In Memoriam," starts with a quick glimpse of Beth Childs (Tatiana Maslany) casually walking into an oncoming train. Maslany's other characters, like Katja Obinger and Rachel Duncan (and her eye), are also featured.

The teaser is like a walk down memory lane for avid "Orphan Black" fans as they once again see characters like Amelia, Brenda, Brenda's son, Dr. Aldous Leekie, Dr. Alan Nealon, Dr. Ethan Duncan, Daniel Rosen, Henrik Johanssen, Paul Dierden, Rudy, Seth, Terry and Tom.

The clip also included a humorous nod goodbye to Donnie's (Kristian Bruun) dignity (he's seen sitting in a chair, shirtless and blindfolded) Gracie's (Zoe De Grand Maison) innocence, Vic's finger, Olivier's tail and Helena's pet scorpion, Pukpok.

Unfortunately, the video also said goodbye to fan favourite Delphine Cormier (Evelyne Brochu), confirming that the character was really killed off. Fans saw Delphine shot during the season 3 finale and had since hoped that she survived somehow

"Orphan Black" showrunners John Fawcett and Graeme Manson never gave a direct answer to fans queries' about Delphine's fate but had admitted to Entertainment Weekly that Cosima and Delphine's love story was destined to be a tragic one. They also said that "this is a horrible thing that had to happen" in order for Cosima's story to move forward.

Aside from Cosima's story, there are other story arcs that are set to be played in season 4. One of them is the introduction of more Castor clones. According to a Design & Trend report, Manson hinted that there's a chance the male clones will find a cure for the illness plaguing them in the upcoming season.

Luckily, fans won't have to wait long to find out what's next for the sestras as "Orphan Black" season 4 is set to return to BBC America in April.