Underground bosses have revealed the full extent of the battle to stop quick-drying cement causing a lengthy shutdown of the Victoria Line.
Services were suspended during last night's rush hour after a tidal wave of foam cement engulfed vital signal equipment at Victoria Station.
The cement was being sprayed into a subterranean cavity as part of a £695m station upgrade when it flooded a signal equipment room.
It was an extraordinary blunder but the consequences could have been worse.
Luckily someone remembered sugar added to wet cement slows the curing process and some quick thinking led to a raid on a local supermarket.
Tube workers then spent two hours scooping up the sweet and sticky and liquid in buckets.
Engineers worked throughout the night to clean and replace the damaged equipment in time for services to resume during this morning.