“A Matter of Time” is episode nine of season five of Star Trek: The Next Generation.
The Enterprise is heading to Penthara IV, where a Type C asteroid has hit an unpopulated continent. Something similar to the nuclear winter Earth experience in the 21st century is expected. Geordi and Data are working on a solution in engineering when Commander Riker checks up on their progress. Climate changes have already been detected and a decrease of 10-12 degrees Celsius is expected in the first ten days.
Captain Picard contacts Riker and requests he come to the bridge. Worf is reporting that they passed close to a space time distortion. Riker arrives on the bridge and is told there’s a small object that wasn’t there before. Sensors can’t penetrate the hull. A hail receives a response and Worf says the captain has been asked to move over. Not the Enterprise, him. Captain Picard walks forward and a man materialises where he was standing. He introduces himself as Berlinghoff Rasmussen (Matt Frewer), a historian from the late 26th century.
In the captain’s ready room, Rasmussen says his speciality is the 22nd to 24th centuries. The captain wants to know why he’s been picked, over anyone else. Rasmussen would love to tell him, but that would change history.
Afterwards, in the observation lounge, Rasmussen says to the senior staff he knows they are aware of the potential of changing the past. He’d like them to complete questionnaires; the captain will determine if there’s a breach of security. Data is asked to escort him to his quarters.
Troi says Rasmussen is holding something back, and not related to potential impacts on the past. As to him being an imposter, he is human, there was a temporal distortion and the ship is unlike anything seen. The captain wants the ship bringing into the shuttle bay and placing under guard, but everything seems in order.
It’s snowing on Penthara IV when they arrive. The plan is to use drilling phasors to release CO2 from underground pockets of the stuff, thereby creating a greenhouse effect. Something the inhabitants have been trying to avoid for years. But tropical rivers are starting to freeze.
Rasmussen arrives in Ten Forward and Dr Crusher invites him to join her, Worf and Riker. The latter not looking so happy at the offer. Rasmussen mentions their assignments; history rarely remembers the activities before important events. Riker asks why there’s no record of other historians. Because they’re careful to remain hidden.
Rasmussen finds Geordi in engineering; Geordi is a little busy to be answering questionaries currently. Data is checking something and Rasmussen asks if that’s as fast as he can do it; little is known of Data’s efficiency. Geordi decides that Rasmussen is here to observe the mission. Rasmussen says he’s just a fly on the wall. A very noisy fly. Geordi contacts the captain and says he’s ready to transport down and Rasmussen pockets a PADD whilst no-one is watching. Which is odd.
Troi doesn’t like Rasmussen and doesn’t trust him. Sometimes, it would be helpful if her empathic senses were a bit more accurate. The attempt to stabilise Penthara IV’s atmosphere looks to have worked., Until it runs into problems. Meanwhile, Rasmussen is wandering around and acting a bit strangely. Which could be explained by him being a time travelling historian, of course.