"Arrow's" Season Four finale seemed to split Green Arrow and Spartan for good, as Diggle's grief and guilt drove him to reenlist in the Armed Forces. However, that parting will soon receive a reprieve, however brief.

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While the premiere episode, titled “Legacy,” saw Oliver briefly talk with Diggle about whether or Green Arrow needed a new team, the season's fourth episode, titled “Penance," will find Oliver joining forces with Lyla to aid Diggle with a secret mission. Meanwhile, Felicity has to decide whether to send the new recruits out on the streets without their leader.

It’s likely "Penance" will include both visual and emotional fireworks, as director Dermott Downs has previously helmed drama-filled "Arrow" episodes like "The Return," as well as some barn-burners for both "The Flash" and "Supergirl." Here's the official synopsis:

ARROW  “Penance” — (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV) OLIVER STEPS IN FOR DIGGLE — Oliver (Stephen Amell) and Lyla (guest star Audrey Marie Anderson) team up on a secret mission for Diggle (David Ramsey). Felicity (Emily Bett Rickards) finds out and disapproves of the plan and opts to stay behind. When Tobias Church (guest star Chad L. Coleman) launches a deadly assault against the city, Felicity must decide if she wants to send the recruits out sans the Green Arrow. Dermott Downs directed the episode written by Brian Ford Sullivan & Oscar Balderrama (#504). Original airdate 10/26/2016.

Airing Wednesdays at 8 pm ET/PT on The CW, "Arrow" stars Stephen Amell, Emily Bett Rickards, David Ramsey, John Barrowman, Willa Holland and more.