In the next episode of "Star Trek: Discovery," a character from the original series may make an unexpected visit.

When viewers finished watching episode 5, there was no preview for the upcoming installment which made them curious. There is possibly a good reason why there was none in order to preserve the surprise. According to Inverse, the title of the next episode is "Lethe." This is in reference to the character of the same name in the original series from the 1960s. It is strongly suggested that the character may appear in "Discovery" and start a new story arc.

In the old episode titled "Dagger of the Mind" from the original series, Captain Kirk (William Shatner) and Dr. Noel (Marianna Hill) beamed down on a planet called Tantalus V to investigate a Federation rehabilitation colony. They discovered that terrible mind experiments were being done on the patients there. One of the therapists was a person called Lethe (Susanne Wasson). She was once a patient there but ended up becoming a counselor. Lethe was very evasive towards Kirk as to why she was brought there as a patient.

In "Discovery," it is hinted that Lethe may make an appearance and shake things up for Captain Gabriel Lorca (Jason Isaacs) and Michael Burnham (Sonequa Martin-Green).

In the last episode, Lorca was captured by the Klingons and tortured on the enemy ship. However, he was able to make his way to a Klingon pod and escape with another Starfleet prisoner. This was not without any obstacles as a couple of Klingon pods chased them and tried to catch the fleeing captives. They were fortunately saved by the Discovery and brought back to their space vessel.

"Star Trek: Discovery" season 1 episode 6 will hit the airwaves on Sunday, Oct. 22 at 8:30 p.m. EDT on CBS All Access.