After reading a magazine article about spotting the signs of infidelity, Gary takes it upon his paranoid self to work out who he thinks Dorothy is doing the dirty with. Armed with a camera, a projector and a pointy stick, he heads out to do some recon work.
Tony is also on a mission to better himself and become less selfish after Debs says she may like him more. After joining an afternoon workshop working with some 'crinklies' Tony then founds out to his dismay Debs has a new boyfriend.