7 Leicester Place - the entrance to what was, for a relatively short period in the mid-60s, the Ad Lib club. The doorway didn't really look like that back then - the whole front "porch" section was added in the 1980s.
The club itself was up on the 4th floor, overlooking the adjacent Lisle Street. Though I've yet to track down any photos of the interior, it was, apparently, all panelled wood, low tables, chandeliers; dark, anonymous; musical policy - exclusively soul/blues/r&b. Strictly for the "movers" and the "shakers", the Beatles had their own table, and the Ad Lib was one of the relatively few places that John felt he could go without being unduly bothered.
This is probably why the participants in the Dental Experience (™) came here on that evening in 1965. One of the most told bits of one of the most told anecdotes centers round the lift, of course:
GEORGE: We went up into the nightclub and it felt as though the elevator was on fire and we were going into hell (and it was and we were), but at the same time we were all in hysterics and crazy. Eventually we got out at the Ad Lib, on the top floor, and sat there, probably for hours and hours.
JOHN: We finally got on the lift. We all thought there was a fire on the lift; it was just a little red light - we were all screaming...
RINGO: I was actually there in the club when John and George got there shouting, "The lift's on fire!"
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The building (and the 4th floor) are now home to offices; blog reader Eric Nernie had an appointment there a few months back, and took these photos of the very elevator in question. (Apparently, it's the original...though it will, doubtless, have been subject to major renovation/replacement of fixtures and fittings etc in the interim.)
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Strangely enough, accounts differ as to why the Ad Lib finally closed in 1966. Some say this was down to the fickle nature of fashion - newer clubs moved into the spotlight, pushing the Ad Lib out of favour. Others claim, however, that the reason it shut was due to...you guessed it - a fire.
*UPDATE*: Julian Carr has just sent me some fascinating information about the club; to wit...there was a fire there, but it happened on November 5, 1964, leading to its temporary closure for repair and renovation due to extensive damage. Now that's interesting, because the date generally ascribed to the Dental Shenanigans(™) is April 8, 1965. The club would not have been long re-opened at that point, and the Beatles would certainly have known about the fire, of course. Hence, coupled with their chemical intake, this was probably the source of red-light related paranoia!
And there's more - the club closed again in January 1966, due to a noise prevention order, before re-opening round the corner in Leicester Square, appended to the 400 Club. The old Ad Lib premises in Leicester Place sparked back into life in November 1970, when the club re-opened there under its old moniker. How long it lasted is unclear, but I believe the 4th floor wasn't converted to an office space before the early 1980s. Anyway, many thanks to Julian for the clarifications and new information.