Jimmy and his guests try to get to the bottom of what laughter is, why we enjoy it so much and what, if anything, it has to do with comedy. Between them, and with the help of contributions from other scientists, they discover that laughter is much older than our species, and may well have contributed to making us human. With professors Sophie Scott, Robin Dunbar and Peter McGraw.
| Name | Type | Role | |
|---|---|---|---|
| Jimmy Carr | Guest Star | Self | |
| Peter Leonard | Director |