Afterwards, they may have brushed their teeth with talking Batman toothbrushes, slipped on their Batman boxer shorts, and settled down in front of a television movie with a bag of bat- shaped tortilla chips. The true devotee may even have been sporting a Batman haircut, skull sprouting the black Bat logo.
The most powerful nation on earth has always been susceptible to exotic crazes, illustrated by its flash-flood love affair with a jug- eared Texan billionaire. But now they are also being nudged towards an infatuation with bats, Batmobiles, penguins, and a sinewy, leather-clad, whip-wielding woman (Michelle Pfeiffer) who goes around meowing and behaving like a cat.
The current fad, known by uninspired headline writers as Batmania, was spawned by the 1989 blockbuster film Batman, the fifth highest grossing film in history. Huge efforts are now being made to revive that success with the release two weeks ago of its sequel, Batman Returns.
In its first weekend Batman Returns made Hollywood history with a record-breaking box office total of dollars 47.7m ( pounds 25m). An estimated 7 million Batfans made it abundantly clear that Gotham City still occupies a special place in the American imagination, an appeal nurtured in childhood by hours of pouring over its dark and shadowy streets in Bob Kane's 1940s comic strip.
Warner Bros, the film's maker, is attempting to cash in on a grand scale. Hundreds of licensed goods, carrying hologram stickers in an attempt to deter counterfeiters, are being churned out in an effort to surpass the dollars 1.5bn generated by themed products, video cassettes, and box office sales by Batman.
However, behind all the razzmatazz, Warner Bros is faced with an embarrassing legal action that again focuses attention on one of the most hotly disputed issues in Hollywood: the dubious manner in which studios handle their book-keeping and distribute their rewards. Two Hollywood producers have filed lawsuits in the Los Angeles Superior Court, seeking damages of dollars 30m from Warner Bros and Batman producers Jon Peters and Peter Guber.
Ben Melniker and Michael Uslan, the film's executive producers, claim they were coerced into striking a 'net profit agreement', instead of receiving a slice of gross profits - a deal enjoyed by the actor Jack Nicholson (The Joker) who made more than dollars 50m from Batman.
The issue has gone to court because Warner Bros has yet to pay the two executives any net profits. The studio has instead made the extraordinary claim that the hugely popular Batman has made a dollars 20m loss, despite earning more than dollars 250m in US ticket sales.
A similar case led humourist Art Buchwald to sue Paramount Pictures over the Eddie Murphy film, Coming to America, which attempted to deny him a share of the profits. Awarding dollars 900,000 damages, the judge condemned Hollywood's net profit system as 'unconscionable'.
The two men, who claim they were the first to come up with the idea for a Batman movie based on the old comic-strip, challenge Warner Bros's claim to have made a loss. They argue in their lawsuits that 'despite at least dollars 200m of profits from Batman, the movie's two creators and executive producers . . . have received not one cent of the movie's stupendous profits'.
Their complaint was drawn up by Pierce O'Donnell, the lawyer who represented Mr Buchwald and is spearheading the assault on Hollywood's net profit payments. 'Fifty years of larceny is enough,' he told the Independent on Sunday. 'The net profit system has been declared illegal and immoral . . . Batman is the fifth highest grossing movie of all time, but these men get nothing.'
He said Batman showed a loss because Warner Bros had 'terribly inflated' its costs by deducting a variety of additional fees - for instance, by adding a 35 per cent distribution fee to the dollars 121m production bill.
Warner Bros has offered the two executives less than dollars 1m as an out-of-court settlement, a sum dismissed by Mr O'Donnell as 'two popcorns and two Cokes'. The switchboard at Warner Bros was closed yesterday, but in an earlier statement the company said that the executives' 'position has not reached a profit point'.
Nor are matters likely to rest with Batman. Messrs Melniker and Uslan are also entitled to 13 per cent net profits of sequels, including Batman Returns, for which they also acted as executive producers. They are certain to argue for their share of every bowl of Batman cereal and every Bat cookie consumed this holiday weekend. 'We don't have the cape; we don't have the mask,' Mr Uslan was recently quoted as saying, 'but we believe we are the good guys.' It will be up to the court to find the Joker.