hacker wearing a Max Headroom mask jammed WTTW's broadcast signal and replaced it with their own audio and video for 88 seconds, concluding with the masked man being hit on his bare butt with a fly swatter. This incident was investigated by the Federal Communications Commission but the culprit's identity was never determined. Once the series ceased production in 1989, the number of stations carrying Doctor Who naturally dropped, although the program's popularity had been waning in the United States for some years. As most stations were in the practice of purchasing the omnibus "movie versions" of the series rather than the fourteen episodes produced annually in its last four years, stations only received four feature-length stories each January. Meanwhile, Iowa Public Television (IPTV), the statewide PBS network for the state of Iowa, saw increased interest in Doctor Who, which was aired on a Friday late-night science fiction marathon alongside Red Dwarf and other British science fiction pieces. IPTV is the only television network (or station, or channel) in the world to have aired Doctor Who virtually continuously from its introduction in 1974 until the present. This totals 35 out of 40 years as of 2014, due to one break of about five years between 1979 and 1984, with other breaks of only a few months or weeks. Proposed Nelvana animated series In 1990, following the cancellation of the live action series, the BBC approached the Canadian animation house Nelvana to propose an animated continuation of the show. The cartoon series was to feature an unspecified Doctor incorporating elements of various BBC series Doctors and was not to be oriented to an audience younger than that of the live action series but was intended to be a continuation of the cancelled series but in animated form in order to save costs but with design elements that would promote merchandise sales. According to Nelvana's Ted Bastien: "We went through a lot of development on it, then we were scripting and storyboarding it and about 4 scripts had been written. It happened really fast". Concept art was prepared depicting several possible versions of the Doctor modelled on actors such as Peter O'Toole, Jeff Goldblum and Christopher Lloyd with elements of the wardrobes of previous Doctors. and new versions of allies such as K-9 and enemies such as the Daleks and Cybermen. The Master was to be "half-man, half robot with a cybernetic