Roache was a henchman of the villainous Doctor Godber, although not as devoted to his causes. He was a vital part in Godber's plan to obtain a secret formula to convert seawater to rocket fuel.
He worked with Godber to help kidnap one of the formula's creators, Professor Borender, and later takes uses a control unit in the Anderbad Tunnel so Lady Penelope Creighton-Ward and Sir Jeremy Hodge can be easily extracted from a train passing through it.
Roache then aides Godber in trying to force the forumula for the conversion from Borender and Hodge, by tying Lady Penelope out in the tunnel for a train to strike her down. However, their plan is hindered when International Rescue's Virgil and Gordon Tracy arrive in the monobrake, and a shootout ensues.
Hodge pleads with Roache, who is still in control of the tunnel's systems, to stop the train to save Penelope. Roache concedes, but before he can do so he is shot by Godber, and presumably dies from his wounds.