Laura Dern needed a ''full security detail'' after appearing in the coming out episode of 'Ellen'.

The 52-year-old actress has hailed playing a lesbian who helped the titular character - who was played by Ellen Degeneres - realise she was gay as the ''greatest thing'' she's ever been part of, though she was warned not to take the role by people who were ''worried'' about the impact it would have on her safety.

She said: ''Greatest thing I could've ever been part of, honestly. An incredible honour....I was excited. I didn't think twice about it. It was a great opportunity. And then the calls started coming in once I'd said yes, from a couple of advisers in Hollywood who were out gay men, [telling me] to not do it. A lot of people in my life really worried. And I was like, 'This is ridiculous.' ''

Laura only realised that not everyone was accepting when there was a bomb threat on set and she felt the ramifications of accepting the role for some time afterwards.

She told Vulture: ''We only did it for what, 10 days? We all spent the next couple of years really struggling in work and safety. It was radical to experience that. It was the only time I ever experienced having to have to have full security detail.''

Although the 'Big Little Lies' star didn't work for a year afterwards, the ''gift'' of the role offered her valuable insight which has influenced her ever since.

She said: ''It's shaped and continues to shape who I am as an advocate, as an activist, as a parent.

''It's a profound thing when you see someone bring their truth, but also all the layers of shame and fear that have been put onto you because of feeling like the other, whatever your experience is. So I'm forever grateful.''