Agent Carter's Leviathan problem will reach its climax in "Valediction."

An Out Of Control Skye, Enraged Mac On 'Agents Of SHIELD'; 'Aftershocks' Promo Previews Dark Times Ahead

The final installment of the eight-episode season, "Valediction" will put an end to the SSR's search for Howard Stark (Dominic Cooper) while Peggy (Hayley Atwell) is faced with the series' big bad.

"Leviathan corners Peggy when she's most vulnerable and the SSR finally close in on Howard Stark!" ABC teased. "Peggy faces the full fury of Leviathan, as Howard Stark makes his return in the explosive season finale of Marvel's Agent Carter."

'Avengers: Age of Ultron' Scarlet Witch & Quicksilver Origins Revealed In Prelude, Are They Inhumans?

If you think you know how to Feb. 24 finale will play out, James D'Arcy (Jarvis) is here to warn you that the series' will take some staggering twists over the next three episodes.

"I'll be honest with you, there's no possible way you can guess how it would play out in the end," D'Arcy told Zap2It. "But we are now starting to hit our stride. I wouldn't say it's a sprint for the finish line quite yet, but it's going to get progressively more and more intense as the episodes continue."

Find out more when Agent Carter airs episode 6, "Sin to Err," on Tuesday at 9 p.m. ET on ABC. Click the video below to see a preview for the series' next episode.