Small red beastie - help please

Small red beastie - help please

Observation - Small red beastie - help please. Description: Found this crawling up the door post. Small, body length about 5mm. Reddy orange in colour. Long antennae. Can't find anything like in my books, so any suggestions would be appreciated.

Found this crawling up the door post. Small, body length about 5mm. Reddy orange in colour. Long antennae. Can't find anything like in my books, so any suggestions would be appreciated.