The ship docks in Libya's rebel bastion of Benghazi and families rush to greet it, anxiously asking the disembarking passengers if they know the whereabouts of their missing loved ones.
"Is he in a prison in Tripoli?" asks Ayman Messaud Digmaa, holding a picture of his brother who was arrested by forces loyal to strongman Moamer Kadhafi in March while he fought alongside the rebels.
His phone rings at the same time, and the family is relieved to learn the news that his brother has been seen by two people, but was not actually on board.
Anxiety is written clear on the faces of those gathered at the port after the rebels said on Sunday that nearly 50,000 prisoners, mostly rebels fighting Kadhafi's forces over the past months, are still missing.
At the dockside, Aisha Sheb is relieved to discover that her daughter, son-in-law and their four children have returned safe and sound from Abu Slim in Tripoli, notorious for its prison and the scene of fierce clashes.
Sheb urges her grandson to chant anti-Kadhafi slogans.
"Do you remember what I taught you over the phone?" she asks. The teenager laughs and chants: "Hey, Curly, it's all over for you!"
Relief is also evident on the face of Ahmed Omar Shakmak, who had been arrested on Tripoli's Green Square and jailed. When asked why, he just smiles and says: "Because, like everyone else, I do not like Kadhafi and his sons."
Signup to our newsletter and follow us on Facebook and Twitter!
"Thank you, God! I got out of prison alive. We had no food or water. I only had God. I owe him my life," adds Shakmak, draped in the new flag of Libya amid the heros' welcome accorded to arriving former political detainees.
Fathi al-Jamaa Majhabi is another survivor who feels lucky to be alive.
Captured early on in the conflict outside the eastern oil hub of Ras Lanuf by Kadhafi's forces, he says he was tortured during the six months he spent in prison.
"They gave me electric shocks in my legs, my arms, all over my body. It was a nightmare. It's unimaginable, but I'm finally free. I'm so happy," says the exhausted man before leaving the dockside, his relatives helping him to walk.
Cries of joy and "Allahu akbar" ("God is greatest") abound as Benghazi welcomes back its children, returning after months of detention in Tripoli.
Dozens of men disembark, many stopping for a moment on the gangway to light a cigarette before stepping once more on terra firma.
Several arriving families with small children, luggage and phones glued to their ears spot waiting relatives in the crowd and rush to join them.
From time to time a cluster of rebel fighters boards the vessel and returns with young men, some still teenagers.
"These are Kadhafi's men. We brought them here to judge them. They'll be treated fairly," says one, guarding five teenagers before they are quickly driven off in a pick-up.