When Mark Hammond searches Charlie's warehouse for clues on Alex's whereabouts, he comes across Charlie's map with interiors marked all over London. One of the interiors listed is the lock-up in Scoresby Street. Mark mentions this to Liam Spencer over the phone and tells him to check it out along with a number of other interiors that Liam writes down. This happens in the mission, Taxi for Mr Chai?. Later in the mission, Filthy Business, as Mark begins to get changed into a telephone repairman in the back of the van, he gets a call from Liam who tells him he's on his way to check if Alex is at the lock-up. Mark points out that if he isn't there, the only place left is Charlie's mansion. It's never actually mentioned or seen but presumably Liam checked out the lock-up and found nothing. Alex