Arc of Infinity

Notes

• The working titles for this story were The Time Of Neman and The Time Of Omega.
• Every story during Season 20 featured an adversary from the past. For this serial, it was Omega, who last faced the first three incarnations of the Doctor in The Three Doctors (1973).
• Colin Baker (who would later succeed Peter Davison as the Sixth Doctor) appeared in the serial as Commander Maxil. It was his performance in this role (which, according to Baker, producer John Nathan-Turner repeatedly told him to "tone down") that first brought him to the attention of the production office.
• Features a guest appearance by Michael Gough (who had previously played the malevolent Celestial Toymaker in the story of the same name). See also Celebrity appearances in Doctor Who.