TV themes ever written—perfect for the show and catchy when heard alone". Morag Reavley of BBC Online argues that the piece is "up there ... in the quintessential soundtrack of the Sixties" with the James Bond films and the songs of Frank Sinatra, Elvis and The Beatles. More generally, he praises the series' "catchy, pulse-quickening tunes", as well as Gray's aptitude for "musical nuance" and the mixing of genres. Heather Phares of Allmusic considers "Thunderbirds Are Go!"—the track accompanying the launch sequences of Thunderbirds 1, 2 and 3—to be a reflection of the mod aspect of 1960s British spy fiction. She also highlights Gray's homage to—and divergence from—musical norms, commenting that his score "sends up the spy and action/adventure conventions of the '60s very stylishly and subtly". David Huckvale identifies Wagnerian homage in both the theme music and the series' premise. Noting that the theme's opening string ostinato is similar in effect to a recurring motif in Ride of the Valkyries, he also likens the Thunderbird machines to Valkyries themselves: "Their function is more benevolent than those warrior maidens, but they do hover over danger, death and destruction." Kevin J. Donnelly of the University of Southampton acknowledges the series' "big-sounding orchestral score", which he compares to that of a live-action film. He also suggests that the music serves partly to draw attention away from the physical imperfections of the puppets. Broadcast history The first episode of Thunderbirds premiered on 30 September 1965 on the ATV Midlands, Westward and Channel franchises of the ITV network. Transmissions by other franchises, including ATV London and Granada, began the following month. Honouring the Andersons' wish for family appeal, many areas showed the series during prime time (typically in a 7.00 p.m. slot). The final episode, the Christmas-themed "Give or Take a Million", was first broadcast on 25 December 1966. Like other British series filmed in colour in the mid-1960s, Thunderbirds was first screened in its home market in black and white, colour broadcasting not starting on the main channels of BBC1 and ITV until November 1969. Despite Grade's decision to double the running time, Thunderbirds was also sold in a two-part, 25-minute episode format. Each "concluding" part began with a narration by Shane Rimmer summarising the first part's action. Granada first showed the series in this format, airing both episode parts on the same night (one before and one after the ITN Evening News).