The upcoming episode of Legends of Tomorrow shows the heroes racing against time to save their younger selves from a deadly assassin, The Pilgrim. Episode 12 of the time-travelling series titled Last Refuge airs this Thursday (21 April) at 9pm EST on The CW.

The official synopsis reads as follows:

Click here to watch the episode online on The CW website.

The promo opens with a look at Faye Kingslee's character The Pilgrim as Rip Hunter says: "Pilgrim is the Time Masters most deadly assassin." Rory adds: "She is hunting our younger selves."

There are a lot of scenes of a young Leonard Snart, as Hunter tells his team: "She can target anyone of you, at any point in time." When Martin says: "If we die in the past...", Hunter adds: "We die in the present." The heroes then race against time to find and save their younger selves. The episode will also reveal Hunter's backstory.

The promo video highlights: "Your history, your past, erased." Arrow's Captain Lance guest stars as Sara's dad. We see Lance trying to protect a young Sara from the Time Masters.

Will the heroes manage to save their younger selves or will they get erased from the timeline? We will have to wait and watch Legends of Tomorrow's upcoming episode to find out.