'Trespassing' hitmaker Adam Lambert has revealed that he attended a special event that was hosted by the Queen of Pop earlier this week and was amazed to watch her party all night long. 

Writing on his official Twitter page this afternoon (June 19), the star explained that he dropped by the afterparty for Madonna's 'The MDNA Tour' DVD film premiere and was so excited to find her there letting her hair down with the other guests as she celebrated the project:

"Dropped by Madonna's #MDNA tour DVD premiere after-party... The Queen of Pop stayed late into the evening just kickin it w everyone. #surreal"

The event itself took place last night at Harlow in New York City and other guests included 'Star Trek' actor Zachary Quinto, Kelly Osbourne and John Travolta. Madonna attended her afterparty wearing a tuxedo and top hat (shown below), which she accessorised with a white silk bowtie and bright red lips. 

Watch Madonna's 'secret project trailer', which was unveiled at the event yesterday, here: