Ben Whishaw says he entered “a gray zone” when he met Norman Scott, the man he portrays in “A Very English Scandal.”

The three-part Amazon series, premiering June 29, recounts Scott’s destructive relationship with British politician Jeremy Thorpe (Hugh Grant), which ultimately destroyed Thorpe’s career when he was tried for (and acquitted of) conspiring to murder Scott.

“We had lunch together so I was able to get a little sense, a flavor, of him,” Whishaw, 37, says of Scott, who he and series director Steven Frears met in London before shooting began. “It’s been really quite complicated talking about it because Norman Scott is still alive and … taking on that role, to a certain extent, I feel like I know Norman because I played him. But I have to keep reminding myself that this man is still very alive and has had a life defined in some ways by this whole story … it’s not just a drama — this is someone’s life.”

The series begins with Thorpe meeting the much-younger Scott (known then as Norman Josiffe) in 1962 at a friend’s country home. The pair embark on an illicit relationship — homosexuality was still illegal in England — before Thorpe breaks up with Scott, who’s self-destructive, emotionally fragile and manipulative. Over the course of its three episodes, “A Very English Scandal” follows both men after the breakup: Scott embarks on a short-lived modeling career and descends into drug use and vagrancy; Thorpe’s political career flourishes (he leads Britain’s Liberal Party) as he weathers the death of his first wife (they have a son) and subsequently remarries.

Through it all, the spectre of his past relationship with Scott continues to haunt Thorpe as their paths continue to cross — threatening to destroy his hard-fought career.

“They were two quite complicated men,” says Whishaw. “I don’t think it’s simply a story about … it being illegal to be gay when they met. I think the interesting thing for me is that you can have some sympathy, to a certain extent, for Jeremy Thorpe, though he goes much further than most of us would dream going. To have that sort of relationship [with Scott] you think is over and then it keeps rearing its head and you seem to be forever attached to one another, even though you’ve finished … I think there’s something most people can relate to about that.

“Norman’s situation is very relatable, too,” he says. “He finds himself in a really extraordinary and appalling situation. I suppose, for me, it’s much more about that messy tangle that human beings can find themselves in in their relationships.

“I really feel that the story as told by [series writer] Russell T. Davies is about these two men who tried to love each other the best they could,” he says. “It went wrong and they spent the next 20 years and all that energy that might have gone into a relationship into something much more destructive, warped, strange and obsessive.

“There was a love there that went wrong that neither man can quite let go of.”

“A Very English Scandal” Series premiere Friday on Amazon