I dont undestand the use of past perfect continuous in this sentence
In an underground laboratory deep beneath the unsuspecting metropolis, a group of rogue scientists had been working together to create a rock’n’roll monster...in their secret Brooklyn lair, the ladies of PARTY LIGHTS had been working day and night to meld all of the greatest qualities of rock’n’roll into one unstoppable sound. ’60s garage swagger, mod pop cool, and fuzzed-out Go-Go’s and Bangles hooks are all in the mix - and this Frankenstein looks pretty damn good in fishnets and hot pants.
I think it is because at the time this description was written they had already finished working , the record was here.
Am I right?
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