The Revolutionary War continues heating up as AMC's period epic 'Turn' heads into its final four episodes of the inaugural season, and Abe Woodhull (Jaime Bell)'s challenges in keeping the Culper Ring afloat grow more dangerous than ever. Before Sunday's all-new installment "Mercy Moment Murder Measure," we have an exclusive first look at the latest AMC episode to 'Turn' heads.

Our exclusive first look at this Sunday's all-new 'Turn' installment sees Caleb Brewster (Daniel Henshall) paying a visit to Abe in order to lay out a new bible, filled with numbers and their corresponding words for Abe to translate the encoded messages hidden from the British. Abe bristles at his alias "Culpepper," at least before learning who chose it for him.

Meanwhile, Here's what AMC had to say of Sunday's "Mercy Moment Murder Measure":

When an old threat returns to Setauket, Abe risks everything to protect Anna. Robert Rogers travels to a prison ship seeking a mysterious man.

Only four episodes remain until AMC's 'Turn' comes to an exciting first season conclusion, so what say you? Will Abe manage to keep the secret long enough for Anna's safety? Check out our exclusive clip from Sundays' "Mercy Moment Murder Measure" above, airing 9:00/8:00 P.M. Central, and give us your predictions in the comments!

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