"Orphan Black" is set to welcome new characters, including a new Leda clone, when it returns for season 4 in April. 

"Orphan Black" lead actress Tatiana Maslany, who plays the role of Sarah Manning, reveals that season 4 will introduce a new Leda clone named M.K., who has been seen wearing a Dolly the Sheep mask in the show's teasers.

Maslany said in an interview on BBC America that the mask represents a lot of things in the show. The new character M.K. will be introduced during the first episodes of season 4.

Season 4 will also show Sarah going out of her Icelandic hideout to find a very unlikely but elusive ally who is closely tied with the death of Beth, whom Sarah stole the identity from in the earlier episodes of the show.

Another new character who will be introduced in season 4 is Evie Cho, who will be portrayed by Jessica Wanlim. Deadline reports that Evie will have a recurring role in the series as a bio-engineer who advocates women's health. Aside from women's health, Evie is also a champion of those are physically disabled and is against sexism.

Although no detail has been given yet as to how Evie will interact with Sarah, it might be through Cosima who got very ill during the last season. Therefore, people speculate that there is a big possibility Evie will help Cosima.

The upcoming season will also reveal more information about Kira (Skyler Wexler), Sarah's daughter.

"Orphan Black" executive producer Graeme Manson said in an interview with The Hollywood Reporter that Kira plays a very important role in the lives of her clones as well as her mother's. Manson continued, "We have definite plans to get more answers about Kira in season four. The most human part about her can't really be explained by science."

The teaser for the show shows Kira telling her mom about the arrival of an unknown group.

"Orphan Black" is scheduled to air on April 14 at 10 p.m. EST on BBC America.