It's time to call in The Cavalry on Agents of SHIELD.

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The ABC family will dive into Agent May's (Ming-Na Wen) past with episode 17, "Melinda," finally answering a mystery that has plagued the series since day 1 - what happened to Wen's character while she was working in Bahrain?

The devastating mission caused May to trade field ops for a desk jockey job, apparently leaving her more laconic and unapproachable than before. Unfortunately, the upcoming revelation will add a new complication to the SHIELD vs. SHIELD battle.

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"The story of Melinda May's transformation into 'The Cavalry' is revealed as she finds herself at a crossroads in the war between Coulson and Gonzales," ABC teased.

"Melinda" will also reunite views with May's ex-husband, Andrew Garner (Blair Underwood). Garner's return will most likely have less to do with managing Skye's new powers and more to do with the fallout from Bahrain that ultimately lead to the dissolution of Agent's May marriage.

"Melinda" will air on April 14.

Find out more when Agents of SHIELD airs Tuesdays at 9 p.m. ET on ABC. Click the video below to see a preview for the series' next episode, "One Door Closes."