Oliver and Diggle go after Thea, while Curtis returns to assist Felicity and Noah

Tonight is the penultimate episode of Arrow‘s fourth season, ‘Lost in the Flood,’ with next week bringing us the season finale showdown with Damien Darhk.

So what can we expect from tonight? Well, luckily The CW has once again supplied us with a collection of sneak preview clips to get us ready.

The first scene (above) sees Oliver and Diggle tracking a message from Thea to discover H.I.V.E.’s secret underground city, which does not go over well with Malcolm Merlyn:

In the next preview, Felicity is still reeling from the loss of 20,000 people in the last episode, when Curtis shows up and meets her father, Noah:

The final clip is an inside look at the episode, with commentary from Arrow EP Wendy Mericle:

Here’s the synopsis for “Lost in the Flood,” written by Brian Ford Sullivan & Oscar Balderrama and directed by Glen Winter:

Following the shocking events in the previous episode, Oliver (Stephen Amell) and Diggle (David Ramsey) race to rescue Thea (Willa Holland), while Felicity (Emily Bett Rickards), Curtis (Echo Kellum) and Noah (guest star Tom Amandes) join together to stop Darhk (guest star Neal McDonough).

Arrow airs tonight at 8/7c on The CW. We’ll have full coverage, including live-tweeting while the episode airs and a full recap tomorrow morning. Be sure to follow us on Twitter, Facebook, and Tumblr for all the latest updates.

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