It was 10 o’clock one night and actress Brooke Hayward had just got her three children settled and was finally relaxing in bed with a book. Her husband, Dennis Hopper, had other plans, however.

He suddenly appeared in their bedroom with Jane Fonda and the actress’s husband, the French director Roger Vadim. The priapic Easy Rider star wanted them to have a foursome.

‘They got into bed with me. I was just furious. I said: “Get the f*** out!” ’ Hayward recalled.

It was certainly not the most conventional domestic behaviour but, then again, the Hoppers would have been horrified to be called conventional. As revealed in a new book — Everybody Thought We Were Crazy by Mark Rozzo — the pair were the uncrowned king and queen of Tinseltown in the Swinging Sixties.

Their Hollywood Hills home at 1712 North Crescent Heights Boulevard — known to many simply as 1712 — became the drug-fuelled beating heart of Los Angeles’ counter-culture scene, where Hells Angels and Black Panthers rubbed shoulders with Andy Warhol, the Rolling Stones and Hollywood stars from Natalie Wood and Jack Nicholson to Paul Newman and Groucho Marx.

In a decade when the champions of ‘radical chic’ regarded the movie industry as irretrievably bourgeois and uncool — the Sound Of Music rather than the sound of rock ’n’ roll — Hopper and Hayward came to the rescue.

Not for nothing were they dubbed the ‘coolest kids in Hollywood’ but, for their own kids, life wasn’t so great.

Hopper, a maverick actor, director, artist and photographer regarded by some as a genius and others as a maniac, managed to destroy every facet of his career with his arrogant and pugnacious behaviour. And the self-described enfant terrible certainly brought his work home with him — his terrified children would often hide from him in cupboards as he hit their mother and brandished a handgun when he went on drug and drink-fuelled rampages.

Hayward managed to stay with him for eight increasingly chaotic and dangerous years before she finally took the children and fled.

‘Those years in the 60s when I was married to Dennis,’ Hayward would recall, ‘were the most wonderful and awful of my life.’

At least she could measure her marriage in years. Hopper’s second marriage, to the beautiful Mamas And The Papas singer Michelle Phillips lasted all of eight days, with her saying she dumped him over his ‘unnatural sex demands’. His first wife knew all about those.

He and Hayward met while performing together in a Broadway play, Mandingo, that was so awful it closed after five days. By then, Hopper — who’d become a teenage star in the 1950s with roles in Rebel Without A Cause and Giant — had moved in with Brooke and her two young sons from a previous marriage.

Their friends were gobsmacked given their drastically different backgrounds. She was Hollywood royalty, the daughter of actress Margaret Sullavan, ex-wife of Henry Fonda, and Hollywood super-agent Leland Hayward.

Her stepmother, the social-climbing socialite Pamela Churchill Harriman, ex-wife of Winston Churchill’s son Randolph, wanted Brooke to marry someone far more elevated than rough diamond Hopper and encouraged Leland to end their romance.

It’s certainly true that Hopper came from a very humble background in Dodge City, Kansas, where his voracious sexual appetite alarmingly extended even as far as his mother, Marjorie. He once admitted that, as he came into puberty, he noticed she had an ‘incredible body’ and he developed a ‘sexual fascination for her’.

In his teens, he had a torrid affair with the man-eating Natalie Wood when, aged 16, she rang him out of the blue after he’d read for a role with her and propositioned him.

The pair later appeared together in Rebel Without A Cause. They and a male friend from the cast once decided to have an orgy in a bath full of champagne only for the alcohol to burn Wood’s crotch so badly she needed to go to hospital. So it’s fair to say Brooke Hayward had her work cut out becoming the first Mrs Hopper.

He claimed he’d warned his wife-to-be that she might be in for a challenging time, telling her: ‘I won’t be easy to live with. I go off on strange tangents. Why, I might not even come home for three days.’ It would be much worse than that.

The couple at least shared a passion for contemporary art. They filled their Hollywood Hills home with cutting-edge artwork, turning it into a ‘surreal fun house’ that served to further entice famous guests to their exotic parties.

Hopper was one of the first people to buy a work by Andy Warhol, one of his Campbell’s soup tin paintings, which his unimpressed wife insisted had to go in the kitchen. In the sitting room, a 14ft devil-like Mexican festival clown strung with firecrackers leered down from the ceiling.

Hopper also had a macabre collection of glass eyes and filled up a bath with dozens of fake heads.

And yet this was a family home in which they were bringing up three young children — Hayward’s sons from her previous marriage and their own daughter, Marin.

The latter says she was ‘terrified’ of an artwork in the living room called The Quickie that consisted of a mannequin head mounted on a skateboard, which she was convinced was a real decapitated head.

Even the couple agreed some of their art was pornographic but never removed it from the house.

Hayward’s son Jeffrey recalled how he and his siblings were too embarrassed to ever bring school friends back. ‘Like everyone else, we wanted to be normal,’ he said. Marin said she felt like she was living with the Munsters.

Hip Hollywood, however, lapped it all up. A Vogue article described the home as ‘a harmonious nightmare of Gothic surrealism’. A constant stream of people, most of them famous, flocked to parties at Chateau Hopper, which were filled with a crowd that was as eclectic as their bizarre art collection.

The writer Joan Didion described it as a place ‘of such gaiety and wit that it seems the result of some marvellous scavenger hunt’, while Andy Warhol compared it to an amusement park (a compliment).

However, the hosts’ passion for inviting round anyone they found interesting had its downsides, particularly when Hopper — as his grand Hollywood ambitions were thwarted — slipped into alcoholism and chronic drug abuse.

Hayward once came upon members of The Diggers, a radical Left-wing political group, ‘cooking up some heroin in the living room’.

Even more alarmingly, Hopper was drawn to the Hells Angels, a hard-living and deeply violent biker gang who some deluded hippies wrongly thought were allies in the battle against the Establishment. The actor would invite them over en masse.

‘I remember waking up one morning,’ said his daughter Marin, then five, ‘and in the living room — they’d moved the furniture back — there were 20 sleeping bags. My mum was like, “Oh, those are the Hells Angels.” ’

If that wasn’t enough to shake any wife’s sanity, there was the sex. ‘My biggest drive wasn’t alcohol or drugs — it was sex,’ Hopper admitted in later life. ‘The idea was to break through inhibitions in order to become a better artist.’

At one point, he said, sex for him became no more remarkable than drinking a beer.

Along with other women who concluded that the sexual liberation of the 1960s only applied to the men, Hayward tolerated his infidelity, asking no questions about the identities of the naked women he loved to artily photograph and even the orgies he regularly attended.

But she drew the line at joining him at the latter. Hopper — who once admitted: ‘I do enjoy group sex’ — reputedly indulged in it regularly with up to 50 women a night. He clearly had a session in mind with fellow sexual athlete Roger Vadim and Jane Fonda, despite the fact that Fonda had been Hayward’s friend since childhood. ‘Can you believe it?’ Hayward told author Mark Rozzo of the incident. ‘That’s just how things were. It was not exactly my idea of heaven.’

To her, says Rozzo, ‘free love was not about freedom or love — it was actually pretty grim, and it had the potential to disrupt precious relationships’.

Hopper did plenty more ‘disrupting’ with his drinking and drug-taking. Hayward believes that his decline into serious alcoholism started when he attended the first hippie love-in in San Francisco. While there, he also got heavily into mind-bending hallucinogenic drugs, such as LSD, acid and mescalin.

When he came home, she said, ‘he had a three-day growth of beard, he was filthy, his hair was crazy — he’d started growing a ponytail, his eyes were blood red. Dennis was altered for ever.’

He was also — by his own admission — smoking at least eight cannabis joints a day and drinking so much that his son Jeffrey said he never saw him without a beer or bottle of Jack Daniel’s in his hand. ‘He smelled like alcohol morning and night,’ he recalled.

One night, Hopper set fire to the bed after lighting a joint and then falling asleep. ‘I woke up, pushed him out of bed. Saved his life,’ said Hayward. ‘He was furious that I called the fire department.’

The actor was terrified the authorities would find his large stash of drugs.

Not long after he returned from the first hippie festival, he did his bit for peace and love by starting to hit her. Fascinated with weapons since boyhood, Hopper would frequently produce a revolver, and often didn’t even bother to hide it from the children. ‘It might be in the car, on the seat, or he’d have it next to his bed on a table,’ recalls stepson Jeffrey. ‘I spent a lot of time hiding in closets.’

He recalled that on one occasion his stepfather ‘chased us with a gun to kill all of us. We were going from house to house, trying to lay low. I mean, it was seriously a psychotic episode’. Their mother tried to reassure them that it was just ‘a great adventure’.

Supremely self-absorbed, Hopper barely functioned as a parent and Hayward struggled to cope. The children started shoplifting. ‘It was a subtle cry for attention,’ said Jeffrey. He was ten when he was handed his first cannabis joint by a member of the rock band Jefferson Airplane at a music festival.

Stoned, he ambled alone at the festival and found the others had deserted him. ‘Oh, we just wanted to go see The Byrds with Hugh Masekela,’ Hopper said to him when they were finally reunited.

By late 1967, Hayward feared for the family’s safety, occasionally evacuating the children to the Chateau Marmont hotel whenever Hopper was ‘on top of the house shrieking or doing something really bizarre’. Jeffrey, only 11, started going to bed clutching a small geologist’s hammer.

Hayward once went to see her husband rehearsing for a play but, when she went to leave, Hopper became ‘completely crazy’, jumping on to the bonnet of her car and kicking in the windscreen while she sat in it, appalled.

Not long after, she was looking through his photos and chose one he didn’t like. He shot out a hand and broke her nose.

In 1968, Hopper and friend Peter Fonda (Jane’s brother) made Easy Rider. The story of long-haired bikers going on a doomed road trip after pulling off a big cocaine deal also featured a young Jack Nicholson. It was hailed as a film-making milestone and Hopper became flavour of the month in Hollywood.

It didn’t last, and nor did his marriage. Returning one evening as Hayward was eating dinner with the children, he threatened to kill her if she didn’t feed him.

Jeffrey stood in front of her and told his stepfather: ‘Don’t you get near my mother.’ She later fled the house with the children, obtained a restraining order against her husband and filing for divorce in 1969.

Hopper would become even more depraved and even more of a wreck, once confessing that he drank ‘a gallon of rum a day, plus 28 beers on the side — then I’d do three grams of cocaine’.

By the time he’d sobered up sufficiently for a second act in his film career, he’d had spells in seven different jails. Married five times, he died of prostate cancer at 74, a very veteran enfant terrible, in 2010. Shortly before, he had a final reunion with Brooke Hayward, during which he told her she was the ‘only woman I ever loved’.

He’d had a strange way of showing it, but then again Dennis Hopper had a strange way of doing almost everything.