The Black Widow is never in the museum (at least not as the Black Widow).
in the expressionism part of the museum
When you have beaten the Black Widow, return to the Museum Fantastique, where the curator will give you the Island Medallion. She will also reveal the secret art treasures hidden in the museum
After you beat the island, you play another island.As to what to do after beating Black Widow, you have to go to the Museum Fantastique to get the Island Medallion from the curator.
Talk to the Curator in the Web Browser cafe, then meet her in the expressionism wing at the museum to get your island Medallion.
Until she kidnaps you in the Inspector's house, the Black Widow is posing as the lady Police Inspector.
The curator is in the Web Browser cafe when you emerge from the lair, but you have to meet her in the museum to receive your Island Medallion.
Talk to the curator as you exit inside the Web Browser Cafe. Return to the Museum to receive the Island Medallion and discover the secret of the Museum Fantastique.
Pick up the Black Widow key card and head back to the museum. You have a package waiting that will send you off Counterfeit Island for a short trip.You have no way to chase him. Return to the museum where you have an important package waiting.
The investigator (aka Chief Inspector) can be found outside the museum, or in her lair after she is revealed as the Black Widow. You get into her lair by using the curator's key to get into her house, then clicking on the peeling corner of the painting.
When you have beaten the Black Widow, return to the Museum Fantastique, where the curator will give you the Island Medallion. She will also reveal the secret art treasures hidden in the museum. *For the full solution to the island, see the related questions below
She sees you at the Web Browser Cafe, which is above the Black Widow's lair, and you should meet her back at the museum to get your Island Medallion.