Doctor Who has a fine tradition of casting excellent guest stars right from the start. The black and white years were graced by high calibre thespians such as Julian Glover in The Crusade and well known actors such as Peter Butterworth as the Meddling Monk and Bernard Bresslaw as Varga the Ice Warrior. The colour years were also graced by some classy guest artists. Who could forget Philip Madoc's Solon in The Brain of Morbius or Tony Bentley's sublime Harrison Chase in The Seeds of Doom? Even when the show was regarded to be on its last legs, it could boast talent such as Ian Hogg, Honor Blackman, Pamela Salem and Sheila Hancock. Since its revival, NuWho has managed to garner an even more impressive roster of talent. From Derek Jacobi's one off Master, Hugh Bonneville's pirate captain, Dougray Scott's professor and Sarah Parish's unforgettable Racnoss Queen, the show is bursting with well known and well regarded names. Famously, 80's producer John Nathan-Turner compared Doctor Who to the Morcambe and Wise show. If asked to be involved, most people say yes. However, it has to be expected that, over the 51 years of Doctor Who's life and its 34 series, not every guest actor has covered themselves in glory. Either because of poor acting skills, bad choices or simply because the role was totally miscast, some actors have become infamous for being particularly bad. Here are 10 examples of when quality control went out of the window.