Alan Rickman and Helen McCrory on their Friendship

An actress known for her work on stage (‘Uncle Vanya’, ‘Twelfth Night’, ‘Medea’), TV (‘Anna Karenina’, ‘Peaky Blinders’, ‘Penny Dreadful’) and film (‘The Queen’, ‘Skyfall’, the final three ‘Harry Potter’ movies), McCrory lives in north London with her husband, the actor Damian Lewis, and their two children

There are a lot of myths about Alan. That he is prickly and unpleasant – because he often plays quite cold, dry people – and that he always wears black. But he couldn’t be further from his screen personas if he tried. And I’ve seen him wear grey at least twice.

I first heard of Alan when I was at drama school. He was doing Les Liaisons Dangereuses in New York [in 1987], hailed in the papers and held up as an example by my teachers at the Drama Centre. We met in 2008, on the set of Harry Potter and the Half-Blood Prince, when Helena [Bonham Carter] and I were playing the Lestrange sisters, and Helena, Alan and I were making a spell “to the death” together.

Though he was brilliant in the part, he wasn’t so method that he swished around in his large black robe in between takes. Instead we’d have a coffee and a giggle – he has a naughty sense of humour – and I’d say, “So, what’s your power again?”

Alan Rickman, 69

An actor, Rickman made his name as Obadiah Slope in the BBC’s 1982 serial ‘The Barchester Chronicles’. He has since won awards for roles in films including ‘Robin Hood: Prince of Thieves’ and ‘Truly Madly Deeply’, and reached a new generation with his role as Severus Snape in the ‘Harry Potter’ films. He also directs at the Royal Court. He lives in London with his partner of 50 years, Rima Horton, an economics lecturer

We properly met on the set of Harry Potter and the Half-Blood Prince, in full costume. Helen with that white stripe in her hair, me with those black buttons and black contacts. Helena was there too. We had a scene with the three of us, nose to nose, having to look threateningly at each other. Helen has a huge sense of the ridiculous and with all that costume and make-up, there wasn’t a hope: we were all trying to behave like grown-ups but laughing to an annoying degree; the producers and crew got a little impatient. It’s run like an army camp there, so I was grateful for those moments of laughter.

With us it’s mostly about laughter and the odd Martini – the two tend to blur into each other. She has a much faster energy than me; she’s on the front foot and I’m not always. But I love anybody who makes me laugh, and her ability is unusually high. She’s witty in an 18th-century way; like Jane Austen, she can pick up a word, play with it and put it down again. She recently talked about lobster sauce sophistication. Where did she get that from?

‘A Little Chaos’ (PG), directed by Alan Rickman and starring Helen McCrory, is out on 17 April