"Arrow" sent reverberations that gave birth to a million questions when Oliver Queen accepted the offer to become the head of the League of Assassins. In order to save his sister, Thea, the green-hooded vigilante was forced to accept it in order to use the Lazarus Pit to resurrect his sister. Will Oliver go to the dark side completely? Has he given up being Arrow completely?

As per TVGuide's official episode description, Oliver Queen will undergo a rigorous metamorphosis as heir to the Demon. He will be unrecognizable as he is now a member of the League of Assassins and must do horrible things before taking Ra's place.

In "Al Sah-Him", Ra's Al Ghul instructs Oliver to go after his daughter, Nyssa, who one once the supposed heir to the Demon. Oliver must eliminate the outcast as per Ra's order. Nyssa is aware that her father will come after her one day, and prepares to fight alone. While training Laurel, the League of Assassins comes after her.

However, Laurel, who has struck a friendship with Nyssa, does not want her to suffer at the hands of her father. She asks Diggle and Felicity to help her. Christian Today reports that Laurel will debut as the Canary Cry and don the suit that Cisco helped her make. Unfortunately, Diggle is caught during the fight and taken to the headquarters of the nefarious organization.

In the promotional clip, Ra's orders Oliver to eliminate Diggle. Diggle is the one person Oliver has come to rely on to make the right decision and helps him keep his humanity intact. Will he kill his brother? Has Oliver Queen gone so dark that he can kill Diggle?

International Business Times speculates that Thea Queen might turn evil after her resurrection from the Pit. A separate TVGuide reports that the Big Bad of season four will be seen in the finale and that Ray Palmer will play a major role. Malcolm and Thea will find closure while Ray and Felicity will get emotional. The season will end in a cliff-hanger.

"Arrow" airs on Wednesdays at 8 p.m. ET on CW.