10 of the Best The Next Generation Guest Stars

For seven seasons of Star Trek: The Next Generation, Captain Jean-Luc Picard and his crew sought out new life and new civilizations across the galaxy. Along the way, they encountered a wild variety of life-forms and space mysteries — everything from an omnipotent being with a penchant for mischief to an ancient Earth novel brought to life on an inhospitable planet. Captain Picard could always rely on his trusty bridge crew, but from time to time a new face would appear. They’d help the ship surpass the capabilities of warp speed or prevent the collision of time and anti-time or flirt with Wesley Crusher in engineering.

Guest stars played pivotal roles in advancing many of The Next Generation’s most memorable and entertaining narratives. Narrowing them down to a Top 10 is a pretty tall order, especially considering who qualifies as a “guest star” has long been open to interpretation. Recurring characters like Q, Guinan, Ro, and Lwaxana Troi became such integral components to the overall Next Gen storyline that I can’t classify them as guests. This list instead is filled with talented actors and other notable figures who beamed on board for one- or two-off arcs. Whether fan favorites, Nielsen darlings, or showcases of star power, these guest stars left lasting impressions long after leaving the Enterprise-D.

Playing the titular rogue in Season 2's “The Outrageous Okona,” Campbell beams over from his malfunctioning cargo ship and gets right to cracking jokes and making dates with the transporter operator (Teri Hatcher). Soon at the center of a he said/she said/he said interplanetary scandal, Campbell is every bit the alluring scoundrel. It’s easy to see how he came this close to being cast as Riker. Campbell’s gone on to success in films like The Rocketeer and the ABC hit Once and Again, but “Okona” remains a dashing and funny sci-fi installment (and also manages to squeeze in Whoopi Goldberg as Guinan and Saturday Night Live alum Joe Piscopo as a Holodeck comic in its B-plot).

Bringing gravitas, wisdom, and a fair bit of cowboy diplomacy, Nimoy appears as Spock in Season 5’s two-parter “Unification.” The episodes are moving in their exploration of two cultures, the Vulcans and Romulans, struggling with their past and future connections. The passing of Star Trek creator Gene Roddenberry was also noted with a tribute card at the start of each episode. In addition to James Doohan in Season 6 and DeForest Kelley in the very first episode of TNG, Nimoy is here to pass the baton, but in his effortless embodiment of an icon in a new story, he reminds you just how rich and expansive the Star Trek world can be.

Portraying a beloved character over the span of multiple decades is no small feat, but Doohan also makes it look easy when Chief Engineer Montgomery Scott appears in Season 6’s “Relics.” In what was the highest Nielsen-rated episode of the season, the Enterprise’s away team finds him maintained within a transporter signal aboard a ship that’s been missing for 75 years. “Relics,” listed as one of the best TNG episodes by both Variety and The Hollywood Reporter, includes a touching moment between two engineering titans. “I’ve always found that a ship is only as good as the engineer who takes care of her,” Scotty tells Geordi, “and from what I can see, the Enterprise is in good hands.”

As Ensign Robin Lefler, a spirited, plucky keeper of tenets, Judd is a whiz in engineering, frequently dropping life lessons in Season 5’s “The Game.” Wil Wheaton is also back as Wesley Crusher, on holiday from Starfleet Academy. Despite the distractions of young love, Judd’s engaging Lefler and Wesley find themselves investigating a mysterious and addictive video game taking over the ship (Lefler Law #17: “When all else fails, do it yourself.”). Rumor has it there was room for more Lefler on The Next Generation, but it never materialized, and Judd was on her way to starring in films like Where the Heart Is and Double Jeopardy.

Have you ever wondered what Albert Einstein, Sir Isaac Newton, and Professor Stephen Hawking might say to one another during a game of poker? Data did, and so the illustrious trio (including the real professor) joined him on the Holodeck in the opener to Season 6’s “Descent – Part I.” In what is still the only Star Trek guest spot by a person playing himself, Hawking revels in his part, especially when getting in a friendly jab at the man who discovered gravity, “Not the apple story again!” Long a fan of the Trek series, the distinguished chair of mathematics at Cambridge University inquired about appearing on TNG while on a visit to the Paramount lot. Who’d he ask about the gig? His host for the day, Leonard Nimoy!

Season 6’s “Second Chances” is full of many things — deep-space yoga, two Rikers — but it also features a cameo by a pioneering NASA astronaut. Waiting to beam down to Nervala IV, Worf, Will Riker, and Thomas Riker are given an update about their transport window by Lt. Junior Grade Palmer, as played by Mae Jemison. In 1992, Jemison became the first African-American woman in space when she flew aboard the shuttle Endeavour as a science mission specialist. A longtime Star Trek fan, Jemison was offered the guest spot opportunity when LeVar Burton, who directed “Second Chances,” learned that she loved the show. Though her time on-screen is brief, it’s a sweet moment celebrating a trailblazer in the exploration of space.

In a shocking twist of fictional fate, Lt. Tasha Yar (Denise Crosby) returns to life via some marvelous guest casting in Season 3’s “Yesterday’s Enterprise.” An alternate reality engulfs the ship via a temporal rift, but only Guinan can tell that things are not right, particularly the presence of the chief of security from Season 1. Crosby slips seamlessly back into the confident and competent Yar in an episode consistently ranked as both a fan and critical favorite. As she navigates the tactical challenges facing the Enterprise-D and Enterprise-C, there’s even time for a little romance with fellow guest star Christopher McDonald.

Can a special envoy who travels inside a Class 8 probe and wears multicolored pleather from head to toe be anything other than badass? Suzie Plakson’s K’Ehleyr, half-human/half-Klingon, is witty, self-assured, and the perfect foil for Worf. Plakson appeared in two episodes as K’Ehleyr (and in Season 1 as a Vulcan!). Season 2’s “The Emissary” gives a notably nuanced glimpse into Klingon love and romance, something both complicated and packed with calisthenics (courtesy of Worf’s Masters of the Universe-style Holodeck fitness program).

Echoes of McCarthyism run through Season 4’s “The Drumhead,” which features the legendary Simmons playing an admiral in search of a saboteur aboard the Enterprise. Simmons, the star of such classic films as Guys and Dolls and Spartacus, commands the screen, searching for a conspiracy that may or may not exist. Anchored by her powerful performance, “The Drumhead” is a compelling reminder of just how easily facts and reality can be manipulated.

In “I, Borg” fromSseason 5, Del Arco takes Third of Five, to a place none of his comrades had gone to before — grappling with his humanity. As Hugh, a Borg wrestling with increasing self-awareness, Del Arco imbues the drone castoff with a quiet dignity in one of the most critically acclaimed episodes of the series. Hugh’s fate ultimately becomes a source of moral debate both in “I, Borg” and when he appears again, in season seven. Continuing Hugh’s journey in the new Star Trek: Picard has only added to the emotional heft of one of the most unique TNG characters.

From 178 episodes of interstellar voyages and interpersonal dramas, choosing the best guest stars from The Next Generation is tricky at best and ultimately just impossible. How could I leave out Howie Seago thriving and struggling with disability as the mediator Riva? Fionnula Flanagan as Data’s long-lost mother? Bebe Neuwirth with a Malcorian-human proposition for Riker? Ten is not enough for a show that boldly went in search of new life, new civilizations, and new stories to expand the human experience.

This article was originally published on August 14, 2020.

Catherine L. Hensley (she/her) is a freelance writer and editor. She’s the author of the novel New York Dolls and is newly obsessed with the idea of a K’Ehleyr origin series. Follow her on Twitter, @NYDollsTheNovel.

Star Trek: Picard streams exclusively on Paramount+ in the U.S. and is distributed concurrently by Paramount Global Content Distribution on Amazon Prime Video in more than 200 countries and territories, and in Canada it airs on Bell Media’s CTV Sci-Fi Channel and streams on Crave.

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