Sliders

The Doctor is a Time Lord: a 900 year old alien with 2 hearts, part of a gifted civilization who mastered time travel. The Doctor saves planets for a living—more of a hobby actually, and the Doctor's very, very good at it.

At Deep Space Nine, a space station located next to a wormhole in the vicinity of the liberated planet of Bajor, Commander Sisko and crew welcome alien visitors, root out evildoers and solve all types of unexpected problems that come their way.

The adventures of The Doctor, a time-traveling humanoid alien known as a Time Lord. He explores the universe in his TARDIS, a sentient time-traveling spaceship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, The Doctor faces a variety of foes while working to save civilizations, help ordinary people, and right many wrongs.

A Librarian from the past time travels to the present and finds himself stuck here. When he returns to his castle, which is now a museum, he inadvertently releases magic across the continent. He is given a new team to help him clean up the mess he made, forming a new team of Librarians.