 extension AppCoordinator: ShelfViewControllerDelegate {
     
     func shelfViewControllerDidSelectPlay(_ controller: ShelfViewController) {
-        guard let viewModel = videosController.detailViewController.viewModel.value else { return }
+        guard let viewModel = controller.viewModel.value else { return }
         
         do {
             let playbackViewModel = try PlaybackViewModel(sessionViewModel: viewModel, storage: storage)

            
            currentPlayerController = VideoPlayerViewController(player: playbackViewModel.player)
            
            attachPlayerToShelf()
        } catch {
            WWDCAlert.show(with: error)
        }

        currentPlayerController = nil
    }
    
    private func attachPlayerToShelf(_ shelf: ShelfViewController) {
        guard let playerController = currentPlayerController else { return }
        
        shelf.addChildViewController(playerController)
        
