Once Upon a Time season 4, episode 16 is all about reunions, but some prove to be more happy than others.

Hook’s deep dark secret is revealed on tonight’s Once Upon a Time season 4, episode 16, “Poor Unfortunate Soul.” Since Ursula’s arrival in Storybrooke, the captain has been on edge wishing to keep his plunders from 300 years ago buried. Before Hook can face his past, August is back to strike a deal in his future.

Previously on ‘Once Upon a Time’

Regina put on her best Evil Queen face and took a stroll down memory lane with Maleficent, Cruella, and Ursula. After convincing them of her unwavering loyalty enough, Regina was introduced to the ring leader of their plan, Rumpelstiltskin.

In the past, Regina aided Maleficent in casting aside her insecurities and learned a valuable lesson in patience and perseverance.

Related: Once Upon a Time season 4, episode 15 recap: Firing the first shot

This week on ‘Once Upon a Time’

Hook and Ursula are not the only two trying to dig up information on tonight’s episode. August returns and is subjected to questioning at the hands of Gold and the Queens of Darkness. But does he have the information that will lead them to the Author?

Meanwhile, Regina’s search for her happy ending gains ground after a familiar face walks back into her life. As we saw earlier this week, Robin Hood is back in Storybrooke! But how he arrived still remains a mystery.

Watch previews of tonight’s episode here!

Watch Once Upon a Time season 4, episode 15, “Poor Unfortunate Soul,” tonight at 8:00 p.m. ET on ABC.