Watch Sadisflix. David Attenborough narrates the charming and fascinating story of some real-life animal romantics. There are show-offs and singers, dancers and fighters, stories of undercover affairs and heartwarming devotion. These include a male polar bear that plays hard to get, a lemur whose odour bags him a mate and a lizard who is tender and faithful to the very end. It reveals that animals can be loving, complex, funny and inventive - it is all part of the mating game.