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WARP FIVE: Callum Keith Rennie on Discovery's Gruff First Officer

The Star Trek: Discovery actor talks Rayner's second chance, command style, and more!

SPOILER WARNING: This article contains story details and plot points for the fifth season of Star Trek: Discovery.

Graphic illustration featuring Rayner and the actor who portrays him, Callum Keith Rennie

Getty Images /

Welcome to Warp Five,'s five question post-mortem with your favorite featured talent from the latest Star Trek episodes.

We're only three episodes into Star Trek: Discovery's final season, but the stakes could not be higher. Not long after saving the entire galaxy from the Dark Matter Anomaly, Captain Michael Burnham and the crew of the U.S.S. Discovery is handed a Red Directive mission from Dr. Kovich.

An 800-year-old science vessel was found on the edge of the Beta Quadrant. Aboard that ship is "something vital to the security of the Federation." They are to retrieve that artifact; however, they're not the only ones on the hunt for the artifact's ancient power. While chasing two criminals in the fifth season opener, "Red Directive," Burnham comes across Captain Rayner and the U.S.S. Antares who is also hot on their trail and unwilling to let Moll and L'ak go as easily as the Discovery captain. had the opportunity to speak with actor Callum Keith Rennie on making first contact with Star Trek, demotions and second chances, his approach to Discovery's newest distinguished yet gruff first officer, and more.

Point of First Contact

Callum Keith Rennie as Rayner on Star Trek: Discovery

"Under the Twin Moons"

Like many others, Rennie was first introduced to the franchise with The Original Series in his youth.

"My first contact with Star Trek was watching it on TV with the original," remembers Rennie. "That's the one that I always reference. If it comes on, I watch it still. For me, I did see all of those other variations as they came out, but I held onto my Spock and my Jim Kirk."

For the Love of the Federation

While pursuing Moll and L'ak on a sand runner, Rayner lifts his fist in the air in excitement of the thrill of the chase in 'Red Directive'

"Red Directive"

In "Red Directive," as Burnham and Discovery is in hot pursuit of this season's main antagonists, Moll and L'ak, they soon learn that the Antares captain has been pursuing them for quite some time, and he refuses to let the slippery pair go each time they're within grasp.

When asked how big of a threat Moll and L'ak, as well as the Progenitor tech, pose to the Federation? Rennie teases that more will be revealed in time, "He has a history [with them] that will be explained later."

Speaking on the choices we've seen Rayner make in response to the two criminals, he shares, "That's Rayner's style of command. His is, 'We're to get those people; we're not to make concessions.' There's no other way outside of what he wants to do. His drive is to succeed; 'Pick a thing, I'll go do it.' That's what he knows how to do."

The distinction is clear; Rayner is a gruff, smart Starfleet captain who holds a clear line between commander and crew — he leads, they follow. His approach is, you get the job done and apologize later.

In an earlier discussion with, executive producer and co-showrunner Michelle Paradise noted, "What's interesting about [Captain Rayner] is that he is going to be a bit of an antagonist, but not in a bad guy way. He's going to push Burnham, and we'll get to see new sides of Burnham and new growth in Burnham because of her interactions with him."

He has a storied track record of wartime success. In "Under the Twin Moons," Federation president Rillak has to remind him that times have changed and they're no longer at war. However, the Antares captain sees threats everywhere, arguing that the Breens are in-fighting, the Orions are regrouping, and war is always a possibility. Not only that, Moll and L'ak now have a head start at retrieving a piece of technology with unbelievable power. He wants everyone to stop living in a "candy-colored holo fantasy."

The Fallout of Q'Mau

A hologram of Captain Rayner appears in Discovery's Engineering room to aid Tilly and Adira as they monitor Burnham and Saru's presence on Lyrek in 'Under the Twin Moons'

"Under the Twin Moons"

During Burnham and Rayner's first run-in, while Discovery's captain sabotages the fleeing thieves' ship while on the hull of their ship, she tells the Antares captain to release its tractor beam hold as the enemy vessel's warp bubble is starting to collapse and her ship can't beam her out to safety while she's in the diminishing bubble. Then, while on Q'Mau together, Rayner continues to pursue Moll and L'ak on his own leaving Burnham and Cleveland 'Book' Booker behind; stating he doesn't have time for their "strategic advantages." Rayner plans to thwart their getaway by detonating the explosive charges hidden in a mountain's entrance, risking the potential of harming those living on the settlement of Q'Mau. Burnham reminds him they're on a non-Federation planet undertaking a highly sensitive and classified mission. When the detonation spirals into a fast-moving avalanche that would decimate the local inhabitants, Discovery requests Antares aid them in creating a shield to block the avalanche as there is not enough time to evacuate. However, Rayner holds off on letting Antares leave orbit at the risk of allowing the two thieves to evade them again.

When Rayner is held accountable for his actions as Federation Headquarters holds an inquiry to the events on Q'Mau. Despite his commendable 30 years of service to Starfleet, and his longstanding friendship with Admiral Vance, the Antares captain was forced to take an early retirement.

"Here's a guy who's been in command for 30 years," Rennie distills. "He goes in to help Burnham and her crew, and then the next thing you know, he's dismissed. So, all of that is bad. If he didn't show up to participate in any of that, he would still just be running his own crew and doing his own thing. He'd be happy on the Antares until the end of time. But he went to help, he made a decision that caused a problem, and then he was fired, sent out to pasture, and he has to make a decision to go, 'Am I done or am I not done?'"

Second Chances and Second Contacts

A Ferengi bartender prepares a drink for a pensive Rayner who sits at the bar in the Discovery lounge in 'Jinaal'


Valuing Rayner's aid he provided her crew while she was on Lyrek, Captain Burnham tells Rayner she'd like for him to be part of her crew — her first officer position has opened up — and she knows he's not ready to end his Starfleet career here. After all, no one understands the value of a second chance more than Burnham herself.

Reflecting on the opportunity presented to his character Rayner, Rennie notes, "He wants to try to be a better person. He's looking at his stuff going, acknowledging at times that he's been too impulsive and doing the the thing that he shouldn't have done, and but doing it anyway."

On his second chance, Rennie adds, "Does he want to be retired or does he still want to be part of the Federation and Starfleet? And he makes that choice, believing, 'What's the worst that can happen? They'll fire me again.'"

An important component of modern Star Trek has been to show the many facets of Starfleet and the Federation. It's not a monolithic institution incapable of faults.

"You do the best job you can at the given moment, and sometimes that works out and sometimes that doesn't," reflects Rennie. "You have to be, 'Well, let's take that risk.' From a commander standpoint, nothing's infallible. There's certain missions that only certain people will be assigned to because of their style. He's the man for the job," before teasing, "You'll soon discover why he's a little harsh at times."

In "Jinaal," while Burnham heads to the surface of Trill to unlock their latest crew, Rayner is tasked with getting to know the senior crew better. While his first impression wasn't great, he now has the opportunity to make a second first impression. Unfortunately for him, his second contact isn't off to a great start when he offers the crew 20 words to provide him insight into them.

It's not going to be an overnight scenario for Rayner to change his ways. "He doesn't want to participate with the Discovery crew the way Burnham wants him to be a team player," he explains. "He's not in that space yet. He's not good at, 'Let's all be friends.' It's not his style."

Joining the Discovery Family

At Discovery's lounge, Rayner looks over towards Tilly as she waits for her drink from the bartender in 'Jinaal'


Rennie's experience joining a series in its final season mirrors Rayner's experience joining a tight-knit crew.

"Coming into a show, you're a new kid in school, you don't know who you're going to be friends with," states Rennie. "You don't know if you're going to get along with anybody. Much like Rayner is there to do his work, I'm there to do my work. But, my [personal] experience was fun. Episode to episode, time spent with everyone, you warm up. There's a warmth that just grows as you move along [with Sonequa Martin-Green and this cast], and you've become part of something."