Stephen Herek, director

I got the Bill & Ted script in the late 80s, after I made Critters. It was apparently Hollywood’s most widely read at the time. Writers Ed Solomon and Chris Matheson had based it on a pair of characters they used for standup comedy. I fell out of my chair laughing. It wasn’t like the John Hughes slice-of-life comedy, it was a bit out-there: two guys from San Dimas who go back in time to research their school history report. I remember saying this is either going to be a huge hit or a huge flop.

Warner Bros wanted to make it for under $10m, but could never budget it for that. So Dino de Laurentiis ended up picking it up. For Bill and Ted, I had an Abbott and Costello dynamic in my head – I think we saw every young guy in LA. Keanu Reeves had this likability about him. He wasn’t even trying to be funny. It was the way he would approach a line: after he said something, he’d have this quizzical look on this face. For our straight man, we boiled it down to 24 guys, and mixed and matched them. Pauly Shore was heavily in the mix, but Alex Winter ended up being chosen.

Monty Python and the Holy Grail’s approach to history was a little bit what I had in mind. We even hired their production designer, Roy Forge Smith. We shot for about 10 weeks, including two in Italy, for just $8.5m – we couldn’t even close the waterpark for when Napoleon hits the waterslides. Anything in that scene in closeup was extras we paid for, but anyone in the distance was a paying waterpark customer. We shot the ancient Greek and medieval segments in Rome, with a foreign crew. I don’t think they understood anything we were doing, but it was a good sign they were laughing on set.

I got a lot of comments like: 'Are there kids who really speak like this?'

Bill and Ted didn’t really have a character arc; it was essentially sketch comedy. So it was hard for Keanu and Alex to keep the energy factor up all the time – what I called the “puppy factor”.

De Laurentiis’s company went bankrupt while we were in post-production, and we had to shop a rough cut around the studios. I got a lot of comments like: “Are there kids that really speak like this?” It was this sweet, funny movie, but it became a hateful experience. I was 30, looking at my career, thinking: ‘I’m done.’ But when they tested it in front of an audience recruited at the malls, people went nuts for the film and there was a bidding war.

It became the sleeper hit of 1989, taking $44m in the US. There have been quite a few similar characters since, like Wayne’s World and Dude, Where’s My Car? It’s a very advanced and rich mine to keep going back to. Bill and Ted are brilliant in their lack of knowledge.

Alex Winter, actor

The Venice Beach look … Alex Winter in the baseball cap with hair protruding. Photograph: Alamy Stock Photo

I met Keanu in my first audition to play Bill. Neither of us thought we would end up actually making the film. You don’t get 90% of the jobs you audition for as a young actor, so we just enjoyed hanging out. We clicked over a couple of superficial things: we both showed up on motorbikes, we both played bass. And we were both from artsy, European, quasi-intellectual families.

Because of our theatre backgrounds, we approached the characters in the same way. At that time, everything was “method” in terms of the sincerity with which you’d look at your character. We were both marrying a clownish-type theatricality with this sincere take. We tried to find the distinctions between them. There’s more of a floppiness to Ted, whereas Bill is making more of a concerted effort to attack the world – but he’s failing completely. It might’ve been why Keanu and I clicked on camera. Often the other actors auditioning would be lampooning Bill and Ted; we were genuinely trying to be in their heads.

I was living in Venice Beach at the time, when there was no one but ex-hippies and skate punks there. I pulled lots of stuff from the local community. The backwards baseball cap thing with the giant shock of hair through the front was a direct lift from a kid who used to be on my street: it had always cracked me up. The crop top was all the wardrobe people, although it was my idea to draw a Wyld Stallyns symbol on the back with a marker.

We didn't mess with their language: it's very floral, not how you'd think dumb Valley guys would speak

The British comedies I loved growing up in the UK were in my head – Peter Sellers, Spike Milligan, that sense of play and silliness. Like when we’re in the armour in the castle and start doing the Star Wars fight with each other. It just seemed like what Bill and Ted would do. We didn’t mess with Ed and Chris’s language, though: it had so much going on in the rhythm. It’s very floral, so paradoxical to how you think dumb Valley guys would speak.

I was in Austin the weekend the movie opened and walked into a diner to get change, and the whole place went crazy. It’s been like that for 30 years now. I get it every day, from all ages. Maybe it’s because Bill and Ted are written completely without cynicism.

We’re in the pre-production on a third film. Chris and Ed wrote it in exactly the same style as the first two, but we’ve had the same response we had to the first two: mainstream Hollywood has turned its nose up, and the studios were like: “This is weird.” We said: “Correct, it’s a Bill & Ted movie.”