I'm having issues with switching xib's when I try to from my second view into the third.

I get into the second view from the first like this...

-(IBAction)startButtonClicked:(id)sender{

    Number2ViewController *screen = [[Number2ViewController alloc] initWithNibName:nil bundle:nil];
    screen.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
    [self presentModalViewController:screen animated:YES];
    [screen release];

    }

But when I'm in the second view trying to get to the third view, the app crashes...

-(IBAction)nextButtonClicked:(id)sender{

    Number3ViewController *screen = [[Number3ViewController alloc] initWithNibName:nil bundle:nil];
    screen.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
    [self presentModalViewController:screen animated:YES];
    [screen release];

    }

I know how to go into one view and then immediately back using

[self dismissModalViewControllerAnimated:YES];

How do you just keep going to different views though without having to go back first?