During Star Trek’s long televison run, there has been plenty of stand out episodes, but for me, none more so than the crossover episodes.
These are where characters from either Star Trek series or movie turn up in another series or movie, such as Captain Picard on DS9 giving Commander Sisko his mission orders.
There have been 28 such occurances where this has happened for a main character, and a handful for recurring guest characters (Gul Evek springs to mind – see Keeping Up With The Cardassians – Part 8 – Gul Evek).
Other guest characters would have been Gowron, Lursa and B’tor, Lwaxana Troi, Vash and Alexander Rozhenko, all started life in TNG and were seen again in DS9. Reg Barclay from TNG would later appear in a few Voyager episodes.
By far the most crossed-over characters are Worf, due to his leaving the Enterprise for DS9 and his subsequent return in all three TNG movies, and Deanna Troi, who appeared in three Voyager episodes and the finale of Enterprise
Among these episodes and movies, there are some really good stand-out crossovers, particularly the appearance of Spock in “Unification” (TNG), Sarek, in the same episode as well as his self titled episode “Sarek” (TNG), Hikaru Sulu in the Voyager episode “Flashback” (VOY) and of course, the DS9 crew going back in time to the USS Enterprise and meeting Kirk, Scotty and co. in “Trials and Tribble-ations (DS9). (Interestingly, Sulu does not appear in this episode)
There has also been those crossover’s that just didn’t work, in particular, the Star Trek Enterprise finale “These Are The Voyages” (ENT).
Below is a list of all crossover episodes that feature main characters from one series or movie in another, although the Voyager episode “False Profits” features the two Ferengi, Arridor and Kol, that were first seen on the TNG episode “The Price”. (The Ferengi were left behind in the Delta Quadrant when the Enterprise negoiated trade rights through the short lived Barzan wormhole).
ENT – BROKEN BOW – features Zefram Cochrane making his “to boldly go” speach just after the events of the movie “First Contact”
And here’s the list in chronological order!
TNG – ENCOUNTER AT FARPOINT – Admiral Leonard McCoy is on board the USS Enterprise-D for an inspection.
TNG – SAREK – Spock’s father Ambassador Sarek of Vulcan is called aboard the USS Enterprise-D to fulfill his latest diplomatic duty, a treaty with a mysterious race known as the Legarans.
Sarek first appeared in the TOS episode “Journey To Babel” and featured in 4 of the TOS movies.
TNG – UNIFICATION PARTS 1 AND 2 – Sarek again appeared in TNG and this time with his son Spock. Spock was secretly conversing with the Romulan people to reunificate the Romulan/Vulcan race’s which diverged thousands of years ago. Sarek is suffering from Bendii Syndrome.
TNG – RELICS – Upon discovering the galaxy’s first Dyson Sphere, the crew of the USS Enterprise-D also come across a face from the past. Stuck in a transporter pattern buffer for over 80 years is former Enterprise 1701 chief engineer Montgommery “Scotty” scott.
DS9 – EMISSARY – Captain Picard boards Starfleet’s newly aquired space station Deep Space Nine to brief Commander Sisko of his mission to prepare the acceptance of the Bajoran people into the Federation. Chief Miles O’Brien says his goodbyes as he prepares to leave the USS Enterprise-D to take up his new position as Chief of Engineering aboard DS9.
TNG – BIRTHRIGHT PART 1 – Cheif Medical Officer of DS9, Julian Bashir, is studying a strange device in sickbay of the USS Enterprise. Data detects the unauthorised access to the computer’s bio-imaging systems and proceeds to investigate. Picard and Dr Crusher are on board DS9 as are Worf and La Forge.
TNG – FIRSTBORN – Riker bribes information out of Quark on Deep Space 9 as to what the Duras sisters are doing and where they are.
TNG – ALL GOOD THINGS… – Chief O’Brien returns to the Enterprise-D from DS9.
Not strictly a crossover as the events involving O’Brien are flashbacks Picard has from his past memories.
ENT – THESE ARE THE VOYAGES – features Commander Riker and Counsellor Troi on a holodeck simulation of the NX-01, where they recreate the founding of the United Federation of Planets speach given by Ambassador Archer.
These events are shown to take place during the time of the TNG episode “The Pegasus”
VOY – CARETAKER – DS9’s resident bartender is trying to sell merchandise to Tom Paris and Harry Kim, two officers aboard the Federation’s newest starship, the USS Voyager. They have arrived at DS9 in search of a Maquis ship that secretly has a member of her crew aboard. The Maquis ship and the USS Voyager vanish from the Badlands and end up 70.000 light years away in the Delta Quadrant.
DS9 – DEFIANT – When Commander William T. Riker from the Enterprise arrives on Deep Space 9, he takes a liking to Kira, who gives him a tour of the Defiant. But Riker is revealed to be not who he claims to be when he attacks Kira and steals the ship. This is actually Riker’s transporter double, Thomas Riker, who has joined the Maquis.
MOV – STAR TREK GENERATIONS – In the late 23rd century, the USS Enterprise-B is on her maiden voyage, and Kirk is no longer in the captain’s chair. The ship must rescue El-Aurian refugees from a mysterious energy ribbon, but the rescue seemingly costs Kirk his life. Seventy-eight years later, one of the El-Aurian survivors leads the crew of the Enterprise-D into a deadly confrontation with the Duras sisters as he plots to re-enter the paradise of the ribbon that nearly destroyed him years prior. Kirk and Picard have to work together to save the galaxy once more.
The Enterprise-D did not survive this movie.
DS9 – THROUGH THE LOOKING GLASS – In the mirror universe the Terran Rebels are fighting the Klingon/Cardassian Alliance, and with them is a mirror version of the USS Voyager’s Commander Tuvok.
DS9 – THE WAY OF THE WARRIOR – After a group of Klingon Warriors arrive at DS9 to protect the Alpha Quadrant from the Dominion, Starfleet dispatch Lt.Cmdr Worf to help Sisko figure out the Klingon’s true intentions.
VOY – DEATH WISH – Two for the price of one in this episdoe, where we see the return of Q in his first outing on board the USS Voyager, where he tries to stop another Q from committing suicide. Along the way, Q brings in Commander Riker, explaining that if it wasn’t for his interference, Riker would never have been born.
VOY – FLASHBACK – After suffering from a series of visions, Tuvok mind melds with Captain Janeway in an attempt to solve his issue. In doing so, he and Janeway are transported back to the time Tuvok served on board the USS Excelsior during the Klingon Peace Conference, and to his former Captain, Hikaru Sulu.
As well as Sulu other characters seen here are Janice Rand and Valtane, all first seen in the movie The Undiscovered Country.
DS9 – TRIALS AND TRIBBLE-ATIONS – When Temporal Investigations arrives on Deep Space 9, Sisko recounts how he and the crew of the Defiant traveled back in time to the 23rd century to prevent the assassination of Captain James T. Kirk during the original Enterprise’s mission to Space Station K-7
MOV – STAR TREK FIRST CONTACT – During a Borg invasion of sector 001, every available starship is tasked with defending Earth, all except the USS Enterprise-E. Disobeying orders, Picard heads to Earth and arrives just as the USS Defiant is heading for a collision with the Borg ship. The Enterprise beams the Defiant’s crew aboard and one Klingon Commander insists on coming to the bridge…welcome back Mr Worf. Also the EMH makes a cameo and advices Borg on implant irritation.
DS9 – DR BASHIR I PRESUME – Doctor Lewis Zimmerman, Director of Holographic Imaging and Programming at Jupiter Station, arrives on Deep Space 9. He was the designer and template for the innovative Emergency Medical Hologram (EMH). He hopes to use Doctor Bashir as the basis for the new Long-term Medical Holographic program (LMH), designed to replace medical staff on distant or isolated outpost.
VOY – TIMELESS – A failed attempt to return home results in Voyager crash-landing on an ice world and also in the deaths of the crew, except Chakotay and Harry Kim. Now, fifteen years later, the two men, having resigned from Starfleet, attempt to alter history to save the ship from disaster before Starfleet can stop them. They are pursued by Captain Geordi La Forge of the Galaxy class USS Challenger.
MOV – STAR TREK INSURRECTION – Another appearance of Worf back into the TNG movies, but we don’t really know why Worf is on board the Enterprise-E.
VOY – PATHFINDER – When the Enterprise-E returns home to Earth, Lieutenant Barclay seeks Counselor Deanna Troi’s help when he worries that he has become obsessed with the crew ofVoyager.
VOY – LIFELINE – Barclay contacts the USS Enterprise-E and speaks to Commander Deanna Troi, the ship’s counselor. He asks her to come to Jupiter Station and provide some insight into the situation between Voyager’s EMH and Dr Zimmerman.
VOY – INSIDE MAN – The Pathfinder Project makes contact with Voyager again… and this time they transmit a hologram of Reginald Barclay to interact with the crew. Showing signs of obessive behavour, Barclay once again seeks the advice of Counselor Troi, who is vacationing on a beach somewhere on Earth.
MOV – STAR TREK NEMESIS – After attending the wedding reception of Riker and Troi, Worf hitches a ride to Betazed where a traditional ceremony is planned. Things don’t quite go to plan. Captain Janeway from the USS Voyager orders Picard to Romulus.
MOV – STAR TREK – Spock tries in vain to stop a star from going supernova and destroying Romulus. The resulting singularity swallows Spock’s ship as well as a Romulan mining ship, both reappear in the past and that event alters the timeline to and alternate reality.
MOV – STAR TREK INTO DARKNESS – After the destruction of Vulcan, Spock and the remaining survivors establish a colony on another world, renamed New Vulcan. The alternate Spock contacts the Prime Spock to ask for advice concerning Khan.
Well, thats it. There are some really good episodes up there on that list, lets hope any new series begins in the same tradition.