Star and producer of upcoming How I Met Your Mother spin-off, Greta Gerwig, has promised fans that the show will retain the 'heart and soul' of the original.

The star told E! News, "I've been a fan of this show since really early on. I've seen every episode. It's [How I Met Your Dad] funny. It shares the heart and soul with the original show, so it has the sweetness and the funniness."

Gerwig added that the How I Met Your Mother cast have been very supporting of her venture, "They're so nice. I went and I hung out with all the cast and they were like, 'If you can be part of this world, it's crazy fun.' They told me they believed in me, and it was really sweet."