Star Trek: Lower Decks is an American adult animated television series created by Mike McMahan for the streaming service CBS All Access. It is the ninth series in the Star Trek franchise, and was launched in 2020 as part of executive producer Alex Kurtzman's expansion of the franchise. Lower Decks is the first animated series created for All Access, and the first animated Star Trek series since the 1973–74 series Star Trek: The Animated Series. It follows the support crew of the U.S.S. Cerritos in the year 2380.
Tawny Newsome, Jack Quaid, Noël Wells, and Eugene Cordero voice "lower decks" crew members of the Cerritos, with Dawnn Lewis, Jerry O'Connell, Fred Tatasciore, and Gillian Vigman also starring. Characters seen previously in Star Trek also appear, including John de Lancie as Q, Jonathan Frakes as William Riker, and Marina Sirtis as Deanna Troi. The following list includes the main cast of Lower Decks, all guest characters with recurring roles, and a supplementary list of other noteworthy guests.
Overview
= Main cast (credited main cast member) = Recurring cast (3+ appearances in a season) = Guest cast (1–2 appearances per season)
Main characters
Mariner
(voiced by Tawny Newsome) is a human ensign aboard the U.S.S. Cerritos and the daughter of Captain Freeman. Newsome described the character as irreverent and a rule-breaker, though she is actually "very good at all things Starfleet, she just doesn't care" and has been demoted several times. Newsome added that Mariner "just wants to ride her skateboard and eat her piece of pizza in peace, man." Mike McMahan confirmed that Captain Amina Ramsey was her former lover at Starfleet Academy. The namesake for Mariner is McMahan's own sister, Beckett Mariner McMahan. In June 2019, Mike McMahan, the series and character creator, hinted that Lower Decks would feature mainly original characters. The next month, Tawny Newsome was cast as Beckett Mariner, one of those new characters. As for the second season, McMahan also felt the writers did not adequately address LGBTQ characters and relationships in the first season, especially since it was their intention to portray Mariner as bisexual which is never made explicit. He said the second season would address this better. Sometime between the end of Season 2 and Season 3 she begins a relationship with Andorian officer Jennifer Sh'reyan. However, they break up due to a misunderstanding during Mariner's unauthorized interview with Victoria Nuzé. In the end of the Season 3 finale, Mariner shows no signs of getting back with Jennifer. In season 4, Mariner was promoted to Lieutenant Jr. Grade.
Furthermore, for much of the first season, when production was impacted due to the COVID-19 pandemic, Newsome recorded her lines in a recording studio set up at her house. Newsome began recording voice overs for the season in early June, in a recording studio which was not possible in the previous season due to the COVID-19 pandemic. She was unable to record with Quaid, as she did on the first season, due to his commitments filming The Boys.
In the first season of the series, Mariner wants to keep her relation with Captain Freeman a secret to the point of only using her mother's maiden name. In the second episode, "Envoys", Mariner is revealed to be the long-time friend of K'orin, a Klingon warrior. She convinces Boimler to stay at Starfleet after K'orin ditches them on an alien planet and Boimler cannot survive on his own in the environment. When Freeman wants Mariner transferred to another ship in "Moist Vessel", the captain gives Mariner continually harder and harder jobs, hoping she will grow bored and tired of the constant work and give up, then transfer herself. In the next episode, Mariner attempts to convince Boimler that his new girlfriend, Barbara, is an evil alien masquerading as human to seduce and cause harm to him, but instead the two find they have much in common and become friends. In the season finale, Boimler inadvertently reveals to the whole crew Mariner's connection to Freeman, but the mother and daughter make amends and reconnect.