1.Kaley Cuoco (who played Penny) on her first red carpet in 2002:

Kaley Cuoco on her most recent red carpet:

And here's a side by side:

2.Johnny Galecki (who played Leonard Hofstadter) on his first red carpet in 1989:

Johnny Galecki on his most recent red carpet:

And here's a side-by-side:

3.Jim Parsons (who played Sheldon Cooper) on his first red carpet in 2005:

Jim Parsons on his most recent red carpet:

And here's a side-by-side:

4.Kunal Nayyar (who played Raj Koothrappali) on his first red carpet in 2007:

Kunal Nayyar on his most recent red carpet:

And here's a side-by-side:

5.Simon Helberg (who played Howard Wolowitz) on his first red carpet in 2007:

Simon Helberg on his most recent red carpet:

And here's a side-by-side:

6.Mayim Bialik (who played Amy Farrah Fowler) on her first red carpet in 1989:

Mayim Bialik on her most recent red carpet:

And here's a side-by-side:

7.Melissa Rauch (who played Bernadette Rostenkowski-Wolowitz) on her first red carpet in 2006:

Melissa Rauch on her most recent red carpet:

And here's a side-by-side:

8.Sara Gilbert (who played Leslie Winkle) on her first red carpet in 1989:

Sara Gilbert on her most recent red carpet:

And here's a side-by-side:

9.Kevin Sussman (who played Stuart Bloom) on his first red carpet in 2004:

Kevin Sussman on his most recent red carpet:

And here's a side by side:

10.Laura Spencer (who played Emily Sweeney) on her first red carpet in 2009:

Laura Spencer on her most recent red carpet:

And here's a side-by-side:

11.Christine Baranski (who played Leonard's mom Beverly) on her first red carpet in 1995:

Christine Baranski on her most recent red carpet:

And here's a side-by-side:

12.Laurie Metcalf (who played Sheldon's mom, Mary) on her first red carpet in 1993:

Laurie Metcalf on her most recent red carpet:

And here's a side-by-side: