 | Harry H. Corbett | ... | Frank Dolan / ... (13 episodes, 1957-1968) |
| Neil McCallum | ... | Clive Mostyn / ... (10 episodes, 1957-1961) |
| Billie Whitelaw | ... | Gloria / ... (9 episodes, 1956-1971) |
| Ronald Lewis | ... | Alec Waterman / ... (9 episodes, 1956-1970) |
| Ann Lynn | ... | Claire Williams / ... (8 episodes, 1958-1970) |
| Donald Churchill | ... | Frank / ... (8 episodes, 1961-1973) |
| Donald Pleasence | ... | Arthur Gladwell / ... (8 episodes, 1957-1967) |
| Paul Whitsun-Jones | ... | Charles Kellogg / ... (8 episodes, 1958-1966) |
| Katharine Blake | ... | Chris Nourse / ... (7 episodes, 1959-1973) |
| Madge Ryan | ... | Mrs. 'Nana' Weston / ... (7 episodes, 1959-1970) |
| Gwen Watford | ... | Bertha Morris / ... (7 episodes, 1958-1968) |
| Colin Blakely | ... | AS. Walter Edge / ... (7 episodes, 1960-1972) |
| Susannah York | ... | Cecily Cardew / ... (7 episodes, 1959-1972) |
| Paul Stassino | ... | Fortunato / ... (6 episodes, 1957-1966) |
| Aubrey Morris | ... | Felix / ... (6 episodes, 1959-1963) |
| Donald Houston | ... | Art / ... (6 episodes, 1956-1967) |
| Adrienne Corri | ... | Angela (6 episodes, 1956-1960) |
| John Robinson | ... | Det. Sgt. Leith / ... (6 episodes, 1956-1965) |
| Peter Butterworth | ... | Albert Potter / ... (6 episodes, 1956-1962) |
| J.G. Devlin | ... | Dad Greevey / ... (6 episodes, 1959-1974) |
| Richard Pasco | ... | Brian (6 episodes, 1958-1968) |
| Sheila Allen | ... | Andrea / ... (6 episodes, 1958-1961) |
| Rupert Davies | ... | Det. Insp. / ... (6 episodes, 1959-1966) |
| Stanley Meadows | ... | Dr. Norman Jones / ... (6 episodes, 1960-1968) |
| Dandy Nichols | ... | Marjorie / ... (6 episodes, 1961-1973) |
| Pauline Yates | ... | Betty / ... (6 episodes, 1964-1970) |
