Chicago P.D.’s first post-Olympics episode keeps things tight with a single but compelling storyline this coming Feb. 23.

Titled “Still Water” the Upton-centric hour sees Hailey (Tracy Spiridakos) contemplating her career after 10 years on the job. While Platt (Amy Morton) urges her to throw a party to celebrate the milestone, we see a reluctant Hailey take to the streets for a run on a cold winter’s night instead — to “build tolerance” in Upton’s own words.

However, when Upton is witness to a car crash that sees a young couple’s car go over a bridge and into the freezing water, she is called upon to use all of her resilience to brave the icy depths in order to save the car’s occupants.

Alone and battling hypothermia in the water, Upton is faced with an impossible — and seemingly heartbreaking — choice about who to save and who to let go, when she acknowledges she cannot rescue both crash victims.

However, the consequences of her choice will quickly come to haunt the young detective when she realises she may have made a terrible error in judgement.

RELATED | “Still Water” Official Photography

The hour will also see a little more on Platt and Upton’s history as Platt reveals the unpleasant details behind the case that first prompted Hailey to join the force.

Meanwhile, determined to right her wrong, an emotional but driven Upton will find herself challenged to place good detective work above a dark desire for just desserts in the final moment that ironically places her and the crash victim back in the same watery predicament.

The “Still Water” episode of Chicago P.D. airs Wednesday, Feb. 23 at 10 p.m. (ET/PT) on NBC.

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