Howard Attfield
From Tardis Wiki, the free Doctor Who reference
Howard Attfield (1947-31 October 2007) played Geoff Noble in The Runaway Bride. He was signed to reprise the role during Series 4, but died early into production of the season after filming several scenes for DW: Partners in Crime.
As a result, his completed scenes were refilmed with Bernard Cribbins playing a different character, Wilfred Mott, though the footage was later included on the DVD release of Series 4. A line of dialogue referencing Geoff Noble in DW: The End of Time, Part Two was included as a tribute to Attfield.