original passage: Across time and space, the Doctor's many incarnations often find events that pique their curiosity, and try to prevent evil forces from harming innocent people or changing history, using only ingenuity and minimal resources, such as the versatile sonic screwdriver. The Doctor rarely travels alone and is often joined by one or more companions on these adventures; these companions are usually humans, owing to the Doctor's fascination with planet Earth, which also leads to frequent collaborations with the international military task force UNIT when Earth is threatened. The Doctor is centuries old and, as a Time Lord, has the ability to regenerate in case of mortal damage to the body, taking on a new appearance, personality and (from 2017 onwards) gender identity. The Doctor's various incarnations have gained numerous recurring enemies during their travels, including the Daleks, their creator Davros, the Cybermen, and the Master, another renegade Time Lord.
original sentence: The Doctor rarely travels alone and is often joined by one or more companions on these adventures; these companions are usually humans, owing to the Doctor's fascination with planet Earth, which also leads to frequent collaborations with the international military task force UNIT when Earth is threatened.
sentence2: Would someone who perused the imdb page for this TV series expect to find that the majority of seasons only had one or two primary, recurring characters (for the Doctor in the lead, and possibly for a main villain)?
sentence1: Across time and space, the Doctor's many incarnations often find events that pique their curiosity, and try to prevent evil forces from harming innocent people or changing history, using only ingenuity and minimal resources, such as the versatile sonic screwdriver. The Doctor rarely travels alone and is often joined by one or more companions on these adventures; these companions are usually humans, owing to the Doctor's fascination with planet Earth, which also leads to frequent collaborations with the international military task force UNIT when Earth is threatened. The Doctor is centuries old and, as a Time Lord, has the ability to regenerate in case of mortal damage to the body, taking on a new appearance, personality and (from 2017 onwards) gender identity. The Doctor's various incarnations have gained numerous recurring enemies during their travels, including the Daleks, their creator Davros, the Cybermen, and the Master, another renegade Time Lord.