ðɪs kəmˈɪʃən ᵻvˈɛntʃuːəli bɪkˌeɪm ɡʊdbˈaɪ, sˈɛɹə dʒˈeɪn smˈɪθ ðə tˈuːpˈɑːɹt fɪnˈɑːli tə ðə fˈoːɹθ sˈiːzən, tɹænsmˈɪɾᵻd ˌɔn fˈɪftiːn ænd sˈɪkstiːn noʊvˈɛmbɚ tˈuː θˈaʊzənd tˈɛn.
This commission eventually became Goodbye, Sarah Jane Smith the two-part finale to the fourth season, transmitted on 15 and 16 November 2010.