Writer Ian Fryer regards "Winged Assassin" as "Captain Scarlet"s "key episode", stating that no instalment "expresses the horror of the series concept better". He praises the "deadpan" presentation of the original DT-19's destruction as well as the "genuinely thrilling" climax, which he regards as the best of any "Captain Scarlet" episode. He argues that the Mysteron victory " this invisible enemy as a truly formidable opponent" while noting that the episode as a whole "treads a fine line between adult themes and suitability for the young audience". Andrew Thomas of "Dreamwatch" magazine comments that the shots of the reconstructed DT-19 "sat menacingly" on the London Airport runway, "with the controls moving on their own and row upon row of empty seats ... is a chilling one, and sets the pattern for the series." Chris Bentley, author of "Captain Scarlet: The Vault", calls the conclusion "startling", commenting that the Mysteron win greatly increases the tension in later episodes. He contrasts this with episodes of earlier Anderson productions, which "always ended happily, with missions accomplished and lives saved."