Undercover Heart is a six-part British television crime drama series, first broadcast on 1 October 1998, that aired on BBC One. The series centres on an undercover vice squad detective, Tom Howarth (Steven Mackintosh), who goes missing while investigating the murder of a prostitute. His wife Lois (Daniela Nardini), and his best friend Matt (Lennie James), who are also detectives, set out to search for him, but end up falling in love with one another. The series was produced by Liquid Television and created by screenwriter Peter Bowker.

The series also starred Lisa Coleman, David Troughton, Tony Curran, Trevor Laird, Buffy Davis and Leonie Elliott in supporting roles. The series was also screened in Australia in 2004. Notably, the series has never been released on DVD.