Richard E. Grant is so memorable in “Can You Ever Forgive Me?” that it’s a shock to realize he’s only in a fraction of the film.

Fox Searchlight’s “Can You Ever Forgive Me?”centers on biographer Lee Israel (Melissa McCarthy) when she is broke and desperate, and begins forging celebrity letters. Israel has encounters with multiple characters, but it’s the love-hate relationship with friend and accomplice Jack Hock (Grant) that audiences remember, even though he only enters one-third into the film.

To begin research, Grant read Israel’s 2008 memoirs. “It was her voice, in all its scabrous wit, but she was very scant on detail about Jack Hock. It’s a real achievement that [scriptwriters] Nicole Holofcener and Jeff Whitty were able to extrapolate those few hints or suggestions and create a full character.”

He also credits the “brilliant” costume designer Arjun Bhasin. “The film starts in 1991, but he gave me clothes that were neo-Romantic, early-1980s. So they were a little threadbare, and worn by a character who was past his sell-by date. For Jack, the wardrobe was Custer’s last stand to charm his way throughout the world before destitution and/or AIDS got him.”

Grant became a star with his first film, the 1987 “Withnail & I.” Since then, he’s appeared in 50 movies, dozens of TV shows, wrote-directed the 2006 film “Wah-Wah” and penned three books, including “With Nails” (1998), his razor-sharp observations about experience on 10 movies with such filmmakers as Robert Altman, Jane Campion, Francis Coppola and Martin Scorsese.

Because he’s an accomplished writer, does he ever rewrite dialogue?

“Never! I do what’s written on the page. I have enormous respect for writers because I know how brutal writing can be. Some actors don’t know their lines, which is sadly not uncommon, and they ad lib. I always wonder, ‘You think you have the smarts to outwit the writer?’ Unless encouraged to improvise, I don’t.”

After directing “Wah-Wah,” an auto-biographical film about growing up in Swaziland, is it hard to give up control and follow a director?
“Oh, no. You absolutely accept that and give yourself completely. As long as you respect them, which I did hugely in Marielle’s case, then you don’t even think about it. It’s a given.”

Marielle is Marielle Heller, directing her second feature, after the 2015 “The Diary of a Teenage Girl.” Grant admires her for being so “compassionate, kind and nurturing” on a tough shoot, with only 26 days in rough weather in Manhattan.

He also loved McCarthy, whom he hadn’t met. “It’s like dating. You hope it’s going to work, but you don’t know. It was a fast-track friendship onscreen and in real life. I’d meet with her even on the days I wasn’t shooting.

“Her whole center of gravity seemed to shift when she began playing Lee. I think she’s extraordinary, with the subtlety and commitment, without a scrap of vanity or sentimentality. I truly hope Melissa is rewarded.”

Grant should be rewarded too. Despite his great career, he’s never been Oscar-nominated, which is likely to change with “Can You Ever Forgive Me?”
The actor has been in big hits (“Bram Stoker’s Dracula,” “Logan”), big clunkers (“Hudson Hawk”), prestige films (“Gosford Park,” “The Iron Lady”) and a slew of cult favorites, including TV’s “Dr. Who,” “Downton Abbey” and “Game of Thrones.”

Upcoming: the ninth “Star Wars” movie. Can you tell us anything about it?

“Yes! It opens Dec. 19, 2019, and that’s as much as I’m allowed to say,” he laughs. “There is a Fort Knox-like security, on a level I didn’t even know was possible.”