The filming of the third season of "Orphan Black" has reportedly started this month for its return to the small screen in spring 2015.

BBC America turned on the green light for the third season of the hit sci-fi series, and has ordered 10 episodes for an upcoming season. Actress Tatiana Maslany will reprise her multiple roles in the series.

Below are the top 4 things that fans should anticipate in the upcoming third season of "Orphan Black".

Project Castor will be explored

One of the shocking revelations last season was about Project Castor, which is a military operation of male clones. This is after it was revealed that Mark (Ari Millen) is a clone. Surprisingly, Millen was supposed to exit the series in season 2. However, his amazing portrayal of the character made the showrunners decide that he should stay.

Sarah will get Mark's help

The final episode showed Helena being hauled into military custody, while her clone Sarah is unaware of the situation. However, once she discovers what happened to her beloved and trusted clone, she will do the best she can to save her.There are speculations that Mark, who was revealed to be one of the male clones, will play a major role in rescuing Helena with the aid of the Clone Club.

According to rumors, Mark resembles one of the guards who took Helena in. Once Sarah realizes who took Helena, it will only be a matter of time before she devises a plan to use Mark to sneak into the military base to save Helena.

Helena's lover may return

Show's co-creator John Fawcett hinted that Helena's lover may come back next season. In one of his interviews, Fawcett said that one of his favorite scenes last season was when Helena found romance with a tow truck driver played by Patrick J. Adams. This hinted that the creator may have plans to bring back his character. Meanwhile, Adams said that he welcomes the opportunity to make a return appearance.

Felix may be a clone

After Mark was shown to be a clone like Sarah, fans have started guessing who will be the next character to be revealed as a clone. Showrunners stated that they received immense pressure from the fans to turn Felix into a clone because of the character's popularity.