You can often tell the quality of an actor by the company he keeps. Roger Lloyd Pack, who has died of pancreatic cancer, aged 69, was one of those actors who only ever seemed to work with the very best. He became internationally famous by playing Trigger in TV's Only Fools and Horses, but he had a long and distinguished stage career: one that, typically, began with the democratic Joint Stock company under William Gaskill and Max Stafford-Clark in the early 1970s and ended with his memorable performances as Aguecheek and Buckingham in the Shakespeare's Globe productions of Twelfth Night and Richard III, respectively.

I never saw Lloyd Pack do any rubbish. He worked with many of our best contemporary writers (Michael Frayn, Alan Bennett, Jez Butterworth, Patrick Marber) and top directors (Peter Gill, Richard Eyre, Ian Rickson). But if any single person threads its way though his long career, it is Harold Pinter. Lloyd Pack was an archetypal Pinter actor: intelligent, a lover of language and possessed of a strong physical presence, as well as being a cricket-loving socialist. Over the years he appeared twice in The Caretaker (at the Nuffield theatre, in Southampton, and at London's Shaw theatre), in The Homecoming, The Lover and Mountain Language. But two particular Pinter performances are etched on my memory.

Lloyd Pack was one of the original cast of One for the Road when it was performed as a lunchtime play at the Lyric Hammersmith in 1984. Alan Bates was the apparently omnipotent but deeply insecure state official, Nicolas; Lloyd Pack was Victor, the head of an imprisoned, tortured family. With his gaunt features and attenuated frame, Lloyd Pack looked right as the victimised Victor. But, although Victor appears in the final scene badly mutilated, there was a quality of unyielding defiance about Lloyd Pack that raised serious questions about where the real power lay. His long, hard, final stare was unforgettable.

Seven years later Lloyd Pack appeared at the Almeida in the premiere of Pinter's Party Time. This time, he was part of the apparatus of state power in a world where civil liberties were being eroded by conspicuous consumption. What Lloyd Pack gave us was a smooth thug in a Savile Row suit, unforgettable in a barbed exchange with an ex-mistress whose husband he had clearly killed. Revealingly, he said the play was intended as a comment on contemporary England and that the supposedly cryptic Pinter gave every character a clearly defined social background.

Of course, Lloyd Pack did fine work with other writers. I always think of him as the hunched, stooping, ashen Kafka in Alan Bennett's attack on the prurience of biography, Kafka's Dick. An habitual poker player, he was wonderful in the 2007 revival of Patrick Marber's Dealer's Choice, playing a loveless solitary whose whole life was devoted to the card table. Arguably, Lloyd Pack's greatest quality as an actor was emotional intensity, and it came as no surprise to discover that his favourite book was Crime and Punishment. One can only speculate about how extraordinary this fine actor would have been playing Dostoyevsky's divided, self-torturing hero Raskolnikov.