Kiefer Sutherland Kiefer Sutherland

President Heller made the ultimate sacrifice on last week's 24: Live Another Day. But was it all for nothing?

Although Heller (William Devane) agreed to hand himself over to Margot Al-Harazi (Michelle Fairley) in order to prevent the terrorist's further drone attacks on London, Jack (Kiefer Sutherland) warned the president that Margot still might not stop. And based on the exclusive preview clip from Monday's episode (9/8c, Fox) below, Jack may have been right.

24 postmortem: Live Another Day bosses on the 200th episode's "sacrifice"

The action-packed clip shows U.S. and British political leaders watching closely as another of Margot's drones inches closer and closer to London. Fortunately, Jack and Chloe (Mary Lynn Rajskub

) believe they have a lock on Margot's location. However, Jack (who's still flying the helicopter!) has to rely on CIA Agent Kate Morgan (Yvonne Strahovski) to take out a number of armed guards in order to get close to Margot.So, has Margot actually gone back on her word, or are other forces now controlling the drone? Check out 24: Live Another Day Monday at 9/8c to find out. (Watch previous episodes here.)