The first episode introduces us to the Doctor, his ship (the TARDIS), his granddaughter Susan, and Ian and Barbara, two of Susan's school teachers. From there the audience, together with Ian and Barbara, are plunged into the unknown.
The season follows a rough pattern of futuristic stories alternating with stories set in Earth's past. The fact that the series was originally intended to be partly educational is readily apparent, and is reflected in Ian's profession as a science teacher and Barbara's as a history teacher - the result being that explanations can come just as easily from them as from the Doctor.
By the end of its first season, Doctor Who had proved itself a big success, due in no small part to the phenomenal impact made by the Daleks. Opposition to the series within the BBC had been largely silenced - for the time being, at least - and the last two stories made as part of the first production block had been held back to launch a second season on air.
Despite adjustments made in the wake of the Daleks' unexpected popularity, the stories of the first season had quite faithfully adhered to the format originally laid down for the series. There had been a few developments - perhaps most notably, the character of the Doctor had mellowed considerably so that, by the end of the run, there was little doubt that he was a champion for good - but stability had been ensured by the fact that the regular team, both in front of and behind the cameras, had remained unchanged throughout. With the coming of the second season, however, a number of important changes lay in store...