If you've watched any of 'Westworld', you'll know that James Marsden is very well-equipped when it comes to switching and out of different acting modes.

What you won't know, because the show has no way of highlighting it (yet), is that Marsden is also a mighty fine celebrity impersonator and his calling card is a stellar Matthew McConaughey that will make you feel like he's in the room with you.

Marsden sat down for a spoiler-free chat with Stephen Colbert last night about 'Westworld' and being mistaken for other actors of a similar cheekbone structure before wheeling out a McConaughey impression that even McConaughey would be confused by.