Delta 4 is a Typhoon-class submarine owned either directly or indirectly by Le Chein Industries.
In 2018, George Le Chein provides the sub and crew to Marilyn Stark, former captain of seaQuest DSV 4600, with the aim to undermine the United Earth/Oceans Organization (UEO). Le Chein aims to rebuild his once-vast mineral and undersea holdings that were annexed by the nascent UEO for the "New Peace," while Stark wished to exact vengeance against her former ship and crew in response to their betrayal during the 2017 Livingston Trench Incident (DSV: "To Be or Not to Be").
Stark's Command[edit | edit source]
Under Stark's command, she began luring seaQuest into her trap by staging various attacks against civilian population centers. Her first target, Gedrick Power Station, is attacked by Delta 4 with precision, damaging it just enough to incite an ecological issue that the UEO vis-à-vis seaQuest could not ignore. Stark would later attack the Westridge Mining Community in an attempt to lure seaQuest (now suffering from system instabilities by Stark's computer virus), with the intent of finishing off her prey. Instead, Nathan Bridger turns the tables, making use of the options seaQuest has at its disposal, including Darwin.
Delta 4 is destroyed, with some survivors, near Westridge. The fate of Marilyn Stark, as well as Delta 4's missing mini-sub, are unknown (DSV: "To Be or Not to Be").