When "Arrow" returns to The CW for its fifth season, Oliver will be facing challenges as both Mayor Queen and as the Green Arrow. The first episode of the season is titled "Legacy," and will explore both Oliver's legacy as the hero of Star City and Laurel's legacy as the fallen Black Canary.

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Now, The CW released the official episode description for "Legacy," which also introduces the first flashbacks of Oliver's time in Russia. As this is "Arrow's" fifth season on the air (and he was stranded on the island for five years,) this will also be the last season for flashbacks. The Russian storyline this season will finally bring into focus everything Oliver has alluded to up to now about his past before he returned home as the hooded archer.

Check out the full episode description below:

ARROW "Legacy" — (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV)

NEW BEGINNINGS — After Laurel’s (Katie Cassidy) death and the departures of both Diggle (David Ramsey) and Thea (Willa Holland) from Team Arrow, Oliver (Stephen Amell) takes to the streets solo to protect Star City’s citizens as the Green Arrow. With Felicity (Emily Bett Rickards) guiding him from the bunker, Oliver is forced to deal with a city that has become overrun with both criminals and a slew of new (and painfully inexperienced) vigilantes. Watching Oliver try to balance his jobs as both the mayor and also the protector of Star City, Felicity suggests he form a new team, but Oliver resists. However, when a deadly new criminal, Tobias Church (guest star Chad L. Coleman), enters the picture, Oliver realizes the best thing for the city might be a new team of superheroes. Meanwhile, the flashbacks take us to Russia where Oliver faces off against the Bratva.

"Arrow" returns to The CW on October 5.