Ep 21. The Undertaking

Oliver Queen is still reeling from the bombshell dropped on him by his mother, Moira Queen, about her involvement in the Undertaking that shook Starling City. With Diggle's help, they begin investigating the mysterious project. Meanwhile, Laurel Lance is also on the hunt for answers, as she believes her father's involvement in the Undertaking led to his death.

As Oliver and Diggle dig deeper, they discover the Undertaking was a plan to level a large portion of Starling City in order to rebuild it with a cleaner, safer infrastructure. However, the casualties and destruction caused by the plan were unacceptable, and the city was left in shambles.

As they uncover more information, they realize that Malcolm Merlyn, who has been revealed as the Dark Archer, was also involved in the Undertaking. They confront him, but are met with resistance. Meanwhile, Moira begins to feel guilty about her role in the Undertaking and reaches out to the one man who may be able to stop it, Robert Queen.

In the midst of all this, Thea Queen is struggling with her own issues as she deals with the revelation that Malcolm Merlyn is her biological father. She turns to Roy Harper for comfort, but he is preoccupied with his own personal mission to bring justice to those affected by the Undertaking.

As the tension mounts and the truth of the Undertaking is revealed, Oliver must make a decision about whether to continue his quest for justice or to give in to his mother's desperate pleas to keep their family safe.

The Undertaking is a pivotal episode in the first season of Arrow, as it sets the stage for the conflict that continues throughout the series. It showcases the complex relationships between the main characters and their struggle with morality, ethics, and personal priorities. Overall, it is a must-watch for fans of the show.