After a spectacular start to his television career in the 1960s, when he played leading roles in two classics by Dostoevsky, the actor David Collings, who has died aged 79, became a cult favourite of sci-fi fans with weird appearances in UFO (produced by the Thunderbirds team of Gerry and Sylvia Anderson), three Doctor Who sagas and the 1979 supernatural detective series Sapphire and Steel, co-starring Joanna Lumley and David McCallum.

Although he started out on the stage, Collings did not consolidate his reputation there until completing more than a decade of television stardom, after which he was in a string of important roles for the Royal Shakespeare Company.

At the Open Air theatre in Regent’s Park he was a genuinely funny Polonius opposite newcomer Damian Lewis’s firebrand Hamlet in 1994, directed by Tim Pigott-Smith; he had first played a tetchy but benignly well-meaning Polonius for an RSC touring production with Philip Franks in 1987.

Collings was a fine featured, red-haired actor with sensitive blue eyes who was equally good at playing neurotic and sweet-natured characters. On television he also ran a good line in eminent characters from history: Percy Grainger in Ken Russell’s Song of Summer (1968), Sir Anthony Babington in Elizabeth R (1971), John Ruskin in The Love School (1975), William Wilberforce in The Fight Against Slavery (1975) and William Pitt in Prince Regent (1979).

He was born in Brighton, East Sussex, to George Collings, a greengrocer, and his wife, Lillian (nee Parsons). At Varndean grammar school he enjoyed acting but had no thoughts of setting out to be a professional actor and, on leaving, started work as a designer in lettering, inheriting that interest from his father, a keen artist. From 1960 he was happily involved in amateur dramatics for the Withdean Players and the Lewes Little theatre, but then was recommended by the actor Freda Dowie to the director David Scase, who had been appointed to run the Liverpool Rep.

After six months in rep, Collings found himself pitched into television through another unsolicited recommendation, this time from the actor John Slater, who thought he might be suitable casting in a 1964 Play of the Week presentation of Crime and Punishment. Thus he found himself playing the impoverished tragic hero, Raskolnikov, murderer of an old pawnbroker, in a three-and-a-half hour existential epic alongside Steven Berkoff, Peter Bowles, Julia Foster and Sylvia Coleridge.

Five years later, in 1969, he was in another mighty Dostoevsky production, a BBC version in six episodes of The Possessed, as the charismatic rabble-rouser Pyotr Verkhovensky, alongside Rosalie Crutchley, Joan Hickson and Angela Pleasence. In the same year he was the Clerk in a BBC adaptation in seven long episodes of Chaucer’s Canterbury Tales, with Barbara Jefford as the Wife of Bath and Barry Linehan as the Miller.

He made a rare feature movie appearance as a lovable Bob Cratchit in the musical Scrooge (1970), with Albert Finney, in the same year as he was captured by aliens and imbued with superhuman powers in UFO. In Doctor Who he was an alien himself, in a rubber mask, with ideas of blowing up the Cybermen with a home-made rocket in 1975; a robot-phobic, Poul, in a 1977 narrative that found him crawling round the floor and sobbing; and in 1983, Peter Davison having succeeded Tom Baker in the title role, he was mistaken for the good doctor before mutating into a mutant with a wild spaghetti hairstyle.

Facebook Twitter Pinterest Collings as Bob Cratchit in the 1970 film Scrooge, with Frances Cuka as his wife. Photograph: Allstar/Waterbury

Pausing only to play Legolas in Lord of the Rings on BBC Radio 4 in 1981, and a guest appearance in the final wipe-out episode of Blake’s 7, Collings joined the RSC for the first time as Newman Noggs in the 1985 revival of David Edgar’s Nicholas Nickleby on tour and on Broadway. He also appeared in a star-studded chorus in the fine Don Taylor television script of Sophocles’ Oedipus (1986), with Michael Pennington, Claire Bloom and John Gielgud.

For the RSC subsequently, between 1996 and 2001, he played Thomas Cranmer in Henry VIII, Baron de Charlus in Tennessee Williams’s Camino Real, Count Lerma in Schiller’s Don Carlos, Sir Politic Would-Be in Ben Jonson’s Volpone, Cardinal Pandulph in King John and Sancho in Lope de Vega’s Madness in Valencia. You could not devise a more varied roster of roles, but he discharged them all with a bitter charm and watchful, wary eye.

In this millennium, he played a neat double of Sir Henry Green and the Duke of Surrey in Kevin Spacey’s Richard II (2005), directed by Trevor Nunn at the Old Vic, and graced a startling revival of Middleton and Rowley’s Jacobean shocker The Changeling (2006) for Declan Donnellan’s Cheek by Jowl company at the Barbican; the cast also included Will Keen, Olivia Williams and an unknown but tremendous Tom Hiddleston.

A favourite “job” was appearing with his son, Samuel, in Toby Frow’s 1950s revival of Marlowe’s Edward II at the Royal Exchange, Manchester, in 2011; he was old Mortimer and Matrevis while Sam doubled as the king’s lover, Piers Gaveston, and his poker-wielding murderer, Lightborn.

Collings was married firstly to Deirdre Bromfield, whom he met at the Lewes Little theatre, in 1962 (they divorced in 1975), and secondly to the actor Karen Archer in 1983, from whom he was separated, although they remained close friends. He is survived by Karen, by their children, Samuel and Eliza, his daughter, Kate, from his first marriage, and his sister, Nola. He was predeceased by Deirdre and two of their children, Matthew and Bethian.

• David Cressy Collings, actor, born 4 June 1940; died 23 March 2020