When the book was first published, it brought new meaning to the words solicitor and briefs, and sent ripples through the legal world.

Fish Sunday Thinking recounted the escapades of male lawyers and their relentless chasing of female colleagues at a top London firm.

Now, the author has been unmasked, and speculation has been growing about how much of the tale is fact and how much is fiction.

Fish Sunday Thinking was published last month under the pseudonym Alex Gilmore.

The work is mainly about the dread of going into work at a big law firm on Monday mornings, and the bullying Big Fish (hence the title) that the fictitious trainee, Denton Voyle, cannot face, or face becoming.

But what has caught the eye is the book's sexual content: it portrays senior partners as obsessively predatory, promoting women on the basis of breast size and sexual allure rather than legal acumen, and calling in the favours owed.

It tells of a bonding weekend, during which a clutch of male corporate lawyers in a bar lick slices of lemon from the cleavage of a female colleague.

On another occasion, an executive wakes up to find himself in bed with two legal secretaries.

Yesterday, the Daily Mail revealed that Alex Gilmore is, in fact, Paul Wragg, a 26-year-old former trainee at Hammonds, one of the world's biggest law firms.

Daniella Conte, head of communications at Hammonds, braced herself for the tidal wave of calls: "We've nothing to say really. We never comment on speculation, and we are not going to make an exception here." She did add: "I will confirm that Paul Wragg worked here, and left a year ago."

The Law Society was also obliged to steel itself, with press officer Michael Thompson saying: "We're just keeping our heads down. There have been a lot of inquiries, but there is nothing we can say, as either a regulator or a representative of solicitors."

The publisher of the book, Arima of Bury St Edmunds, was caught unprepared yesterday: the entire staff - bar someone assigned to answer the phone - went into conclave at 10.30am and was still there by 4pm.

After having insisted anonymously that his account was based on experience, Wragg changed his tune on being identified, telling the Mail the book was "purely a work of imagination".

Wragg declined to return calls.

Under it's Perfect Partner discount price offer, Amazon has twinned Fish Sunday Thinking with Belle de Jour: Intimate Adventures of a London Call Girl.