Over its seven-season run, Arrow has seen a lot of twists and turns, with the main cast of characters rocked by major deaths throughout the history of the DC TV show. One of series' first truly shocking moments was the brutal death of Sara Lance, when the fan-favorite character patrolled the rooftops of Starling City as the Arrowverse's original Black Canary. The death would dramatically shock the characters to their core as they scrambled as they searched for Sara's killer before discovering the culprit was closer than they realized.

With Arrow's final season quickly approaching, we're taking a look back at the dark murder mystery that shook Arrow  to its core, and all of major players around the death of Black Canary.

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The Death of Sara Lance

Sara Lance's Canary in Arrow Season 2

After being rescued from the sinking ship that stranded Oliver Queen on a remote island for years, Sara was eventually recovered by Nyssa al Ghul and the League of Assassins. Taken to the League's headquarters in Nanda Parbat, Sara trained in martial arts and ninjutsu with League and entered a romantic relationship with Nyssa for six years before returning to Starling City during Season 2. Taking on the mantle of the Canary after her nickname within the League, Sara fought crime and joined Team Arrow after revealing herself to be alive to her family and Oliver.

In the Season 3 premiere, Sara is shot in the chest with three arrows by a shadowy assailant who flees into the night. Sara's sister Laurel takes Sara's body to the rest of Team Arrow whom bury her in secret while swearing to avenge her death as Laurel vows to follow in her younger sister's crime-fighting footsteps. After initially suspecting the assassin Simon Lacroix, the team discovered that the lethal archer was not in Starling City the night of Sara's death, which left the mystery unsolved for a time.

Thea Queen, Innocence Lost

Speedy on Arrow

Between Seasons 2 and 3, Thea Queen had discovered her true biological father was actually Malcolm Merlyn and departed with him to train in archery and martial arts in Latin America. Returning to Starling City at the start of Season 3, Thea was an accomplished fighter and expert with hand-to-hand weapons in her own right who still trusted her father.

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Eventually it was discovered that Thea was actually the mysterious archer that had killed Sara at the start of the season, with Oliver learning the truth and informing his sister about the murder to her visible shock and disbelief.

The True Mastermind

Malcolm Merlyn

After implying to Nyssa that her father Ra's al Ghul killed due to her leaving the League of Assassins, Malcolm is revealed to be the true mastermind behind Sara's murder instead. After his own wife's death, Malcolm had trained under Ra's and the League to gain the skills to avenge her death, leaving Ra's swearing revenge for abandoning them.

To gain revenge against Team Arrow and Ra's and pit the two against each other, Malcolm hooked Thea on drugs while they had been training outside of Starling City, making his daughter more violent and easier to control. While under the influence of the drugs, Malcolm manipulated Thea into killing Sara upon their return to the city, with Thea forgetting her actions shortly thereafter. Upon discovering the truth, Nyssa vowed revenge while the relationship between Malcolm and Thea was ruptured permanently.

Returning Tuesday, Oct. 15 at 9 p.m. ET/PT on The CW, Arrow stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Rick Gonzalez as Wild Dog, Juliana Harkavy as Black Canary, Katie Cassidy as Black Siren, Katherine McNamara as Mia Smoak, Joseph David-Jones as Connor Hawke and Ben Lewis as William Clayton-Queen.

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