Star Trek: Enterprise (originally titled Enterprise until “Extinction”, the third episode of season three) is an American science fiction TV series created by Rick Berman and Brannon Braga as a prequel to Star Trek: The Original Series. The series originally aired from September 26, 2001, to May 13, 2005, on UPN, spanning 98 episodes across four seasons. Set in the 22nd century, the series follows the adventures of the crew of the first Starfleet starship Enterprise, registration NX-01, as they explore the galaxy. An ongoing storyline, referred to as the Temporal Cold War, continued until the start of the fourth season in which forces from further into the future attempted to manipulate events during the time frame of Enterprise. An escalation of this in the third season introduced the Xindi, and dealt with the repercussions of their direct attack on Earth. For the fourth season, Manny Coto was promoted to executive producer and showrunner.

After being asked to produce a fifth Star Trek series by UPN, Braga and Berman sought to create a more basic and relatable series set after the events of the film Star Trek: First Contact. The episodes concentrated on a core trio of characters, Captain Jonathan Archer (Scott Bakula), Commander Charles “Trip” Tucker III (Connor Trinneer) and Sub-commander T’Pol (Jolene Blalock). It was filmed on the Paramount lot in Los Angeles, California, on the same stages which had housed Star Trek series and films since the abandoned Star Trek: Phase II in the late 1970s. In addition to dropping the Star Trek prefix, Enterprise also differed from earlier series in the franchise by using “Faith of the Heart” by Russell Watson as the theme tune. This differed from orchestral themes used in previous series, prompting a negative reaction from fans.

The pilot, “Broken Bow”, was received positively by critics with praise for the writing and the cast and the ratings were good enough that a full seven season order was expected. However, reviews became more mixed as the first season went on and by the following season, critics were calling the series “broken” as the ratings dropped. These reviews improved during the last two seasons, but ratings continued to decline and UPN cut both the initial orders for the third and fourth seasons by two episodes each before cancelling the series in 2005. The finale “These Are the Voyages…” was particularly poorly received by critics, with complaints directed at the inclusion of characters from Star Trek: The Next Generation and the unnecessary death of Tucker. Prior to cancellation, work had already begun planning episodes for the fifth season.

https://en.wikipedia.org/wiki/Star_Trek:_Enterprise