By the time Marlow is met by Amanda Ripley, he has already been locked up aboard the Sevastopol for quite some time. He was detained with several questionable items in his possession, including the flight recorder to the Nostromo. Thanks to Nina Taylor, he is free from his cell and able to force her onto the Anesidora. All in an attempt to make right the decision of bringing the infected Catherine Foster to Sevastopol. Thus unknowingly leading to the onslaught by the Alien. He tried to rationalize his decision to Amanda, but was overtaken by Taylor when he wasn't looking.