Brash, athletic first officer of the USS Cerritos who serves as a demanding mentor to Beckett Mariner.
Jack Ransom, voiced by Jerry O'Connell, is the human first officer of the USS Cerritos in the 2380s. The series' creator compared him to William Riker but with less restraint. He is confident, fiercely competitive and proud of his physique, and he usually leads the away teams.
Ransom spends much of Lower Decks dealing with Beckett Mariner, the daughter of his captain, Carol Freeman. He recognizes Brad Boimler's talent early on and later takes charge of Mariner's probation, with the power to have her discharged if she fails. A misunderstanding over one of her actions contributes to her resignation from Starfleet, and when she returns and decides to take her career seriously, Ransom becomes her mentor, to his dismay. He gradually forms an unlikely bond with the ship's junior officers.
Ransom provides much of the comedy at senior staff level in Lower Decks. Over time the show also gives him moments of genuine leadership and care for his crew.