Molly was a trance worm rescued by Cleveland Booker in the late 32nd century.
In 3188, Molly was being delivered to a holo buyer to be used as food when Cosmo Traitt stole her en route. Booker took her from Cosmo, and was forced to crash land on Hima to gather more dilithium, leaving Molly in a temperature-controlled cargo pod.
Booker, pursued by local Andorian-Orion authorities, tricked them into releasing Molly (using the security code "sticky") after which she tore apart Ithyk and Ithor. She briefly swallowed Commander Michael Burnham, though Booker convinced Molly to spit her out. Booker was then able to deliver Molly to Sanctuary Four, where she was released into a herd of trance worms just in time for their breeding cycle. (DIS: "That Hope Is You, Part 1")
In 3191, after planting the World Root cuttings he got from the Eternal Gallery and Archive on Sanctuary Four, Booker reminded Burnham that it was the same place they took Molly. Having been almost eaten by the trance worm, Burnham found it hard to forget her and was excited to learn that Molly had a baby now. (DIS: "Life, Itself")